PLANTS _continued_--FRUITS--ORNAMENTAL TREES--FLOWERS.
FRUITS.--GRAPES--VARY IN ODD AND TRIFLING PARTICULARS.--MULBERRY.--THE
ORANGE GROUP--SINGULAR RESULTS FROM CROSSING.--PEACH AND
NECTARINE--BUD-VARIATION--ANALOGOUS VARIATION--RELATION TO THE
ALMOND.--APRICOT.--PLUMS--VARIATION IN THEIR
STONES.--CHERRIES--SINGULAR VARIETIES
OF.--APPLE.--PEAR.--STRAWBERRY--INTERBLENDING OF THE ORIGINAL
FORMS.--GOOSEBERRY--STEADY INCREASE IN SIZE OF THE FRUIT--VARIETIES
OF.--WALNUT.--NUT.--CUCURBITACEOUS PLANTS--WONDERFUL VARIATION OF.
ORNAMENTAL TREES--THEIR VARIATION IN DEGREE AND
KIND--ASH-TREE--SCOTCH-FIR--HAWTHORN.
FLOWERS--MULTIPLE ORIGIN OF MANY KINDS--VARIATION IN CONSTITUTIONAL
PECULIARITIES--KIND OF VARIATION.--ROSES--SEVERAL SPECIES
CULTIVATED.--PANSY.--DAHLIA.--HYACINTH, HISTORY AND VARIATION OF.
_The Vine_ (_Vitis vinifera_).--The best authorities consider all our
grapes as the descendants of one species which now grows wild in
western Asia, which grew during the Bronze-age wild in Italy,[615] and
which has recently been found fossil in a tufaceous deposit in the
south of France.[616] Some authors, however, entertain much doubt about
the single parentage of our cultivated varieties, owing to the number
of semi-wild forms found in Southern Europe, especially as described by
Clemente,[617] in a forest in Spain; but as the grape sows itself
freely in Southern Europe, and as several of the chief kinds transmit
their characters by seed,[618] whilst others are extremely variable,
the existence of many different escaped forms could hardly fail to
occur in countries where this plant has been cultivated from the
remotest antiquity. That the vine varies much when propagated by seed,
we may infer from the largely increased number of varieties since the
earlier historical records. New hot-house varieties are produced almost
every year; for instance,[619] a golden-coloured variety has been
recently raised in England from a black grape without the aid of a
cross. {333} Van Mons[620] reared a multitude of varieties from the
seed of one vine, which was completely separated from all others, so
that there could not, at least in this generation, have been any
crossing, and the seedlings presented "les analogues de toutes les
sortes," and differed in almost every possible character both in the
fruit and foliage.
The cultivated varieties are extremely numerous; Count Odart says that
he will not deny that there may exist throughout the world 700 or 800,
perhaps even 1000 varieties, but not a third of these have any value.
In the Catalogue of fruit cultivated in the Horticultural Gardens of
London, published in 1842, 99 varieties are enumerated. Wherever the
grape is grown many varieties occur: Pallas describes 24 in the Crimea,
and Burnes mentions 10 in Cabool. The classification of the varieties
has much perplexed writers, and Count Odart is reduced to a
geographical system; but I will not enter on this subject, nor on the
many and great differences between the varieties. I will merely specify
a few curious and trifling peculiarities, all taken from Odart's highly
esteemed work,[621] for the sake of showing the diversified variability
of this plant. Simon has classed grapes into two main divisions, those
with downy leaves and those with smooth leaves, but he admits that in
one variety, namely the Rebazo, the leaves are either smooth or downy;
and Odart (p. 70) states that some varieties have the nerves alone, and
other varieties their young leaves, downy, whilst the old ones are
smooth. The Pedro-Ximenes grape (Odart, p. 397) presents a peculiarity
by which it can be at once recognised amongst a host of other
varieties, namely, that when the fruit is nearly ripe the nerves of the
leaves or even the whole surface becomes yellow. The Barbera d'Asti is
well marked by several characters (p. 426), amongst others, "by some of
the leaves, and it is always the lowest on the branches, suddenly
becoming of a dark red colour." Several authors in classifying grapes
have founded their main divisions on the berries being either round or
oblong; and Odart admits the value of this character; yet there is one
variety, the Maccabeo (p. 71), which often produces small round, and
large oblong, berries in the same bunch. Certain grapes called Nebbiolo
(p. 429) present a constant character, sufficient for their
recognition, namely, "the slight adherence of that part of the pulp
which surrounds the seeds to the rest of the berry, when cut through
transversely." A Rhenish variety is mentioned (p. 228) which likes a
dry soil; the fruit ripens well, but at the moment of maturity, if much
rain falls, the berries are apt to rot; on the other hand, the fruit of
a Swiss variety (p. 243) is valued for well sustaining prolonged
humidity. This latter variety sprouts late in the spring, yet matures
its fruit early; other varieties (p. 362) have the fault of being too
much excited by the April sun, and in consequence suffer from frost. A
Styrian variety (p. 254) has brittle foot-stalks, so that the clusters
of fruit are often blown off; this variety is said to be particularly
attractive to wasps and bees. Other varieties have tough stalks, which
resist the wind. Many other variable characters could be given, but the
foregoing facts are sufficient to show in how many small structural and
{334} constitutional details the vine varies. During the vine disease
in France certain whole groups of varieties[622] have suffered far more
from mildew than others. Thus "the group of the Chasselas, so rich in
varieties, did not afford a single fortunate exception;" certain other
groups suffered much less; the true old Burgundy, for instance, was
comparatively free from disease, and the Carminat likewise resisted the
attack. The American vines, which belong to a distinct species,
entirely escaped the disease in France; and we thus see that those
European varieties which best resist the disease must have acquired in
a slight degree the same constitutional peculiarities as the American
species.
_White Mulberry_ (_Morus alba_).--I mention this plant because it has
varied in certain characters, namely, in the texture and quality of the
leaves, fitting them to serve as food for the domesticated silkworm, in
a manner not observed with other plants; but this has arisen simply
from such variations in the mulberry having been attended to, selected,
and rendered more or less constant. M. de Quatrefages[623] briefly
describes six kinds cultivated in one valley in France: of these the
_amourouso_ produces excellent leaves, but is rapidly being abandoned
because it produces much fruit mingled with the leaves: the _antofino_
yields deeply cut leaves of the finest quality, but not in great
quantity: the _claro_ is much sought for because the leaves can be
easily collected: lastly, the _roso_ bears strong hardy leaves,
produced in large quantity, but with the one inconvenience, that they
are best adapted for the worms after their fourth moult. MM.
Jacquemet-Bonnefont, of Lyon, however, remark in their catalogue (1862)
that two sub-varieties have been confounded under the name of the
_roso,_ one having leaves too thick for the caterpillars, the other
being valuable because the leaves can easily be gathered from the
branches without the bark being torn.
In India the mulberry has also given rise to many varieties. The Indian
form is thought by many botanists to be a distinct species; but as
Royle remarks,[624] "so many varieties have been produced by
cultivation that it is difficult to ascertain whether they all belong
to one species;" they are, as he adds, nearly as numerous as those of
the silkworm.
_The Orange Group._--We here meet with great confusion in the specific
distinction and parentage of the several kinds. Gallesio,[625] who
almost devoted his life-time to the subject, considers that there are
four species, namely, sweet and bitter oranges, lemons, and citrons,
each of which has given rise to whole groups of varieties, monsters,
and supposed hybrids. One high authority[626] believes that these four
reputed species are all {335} varieties of the wild _Citrus medica_,
but that the shaddock (_Citrus decumana_), which is not known in a wild
state, is a distinct species; though its distinctness is doubted by
another writer "of great authority on such matters," namely, Dr.
Buchanan Hamilton. Alph. De Candolle,[627] on the other hand--and there
cannot be a more capable judge--advances what he considers sufficient
evidence of the orange (he doubts whether the bitter and sweet kinds
are specifically distinct), the lemon, and citron, having been found
wild, and consequently that they are distinct. He mentions two other
forms cultivated in Japan and Java, which he ranks as undoubted
species; he speaks rather more doubtfully about the shaddock, which
varies much, and has not been found wild; and finally he considers some
forms, such as Adam's apple and the bergamotte, as probably hybrids.
I have briefly abstracted these opinions for the sake of showing those
who have never attended to such subjects, how perplexed with doubt they
are. It would, therefore, be useless for my purpose to give a sketch of
the conspicuous differences between the several forms. Besides the
ever-recurrent difficulty of determining whether forms found wild are
truly aboriginal or are escaped seedlings, many of the forms, which
must be ranked as varieties, transmit their characters almost perfectly
by seed. Sweet and bitter oranges differ in no important respect except
in the flavour of their fruit, but Gallesio[628] is most emphatic that
both kinds can be propagated by seed with absolute certainty.
Consequently, in accordance with his simple rule, he classes them as
distinct species; as he does sweet and bitter almonds, the peach and
nectarine, &c. He admits, however, that the soft-shelled pine-tree
produces not only soft-shelled but some hard-shelled seedlings, so that
a little greater force in the power of inheritance would, according to
this rule, raise the soft-shelled pine-tree into the dignity of an
aboriginally created species. The positive assertion made by
Macfayden[629] that the pips of sweet oranges produce in Jamaica,
according to the nature of the soil in which they are sown, either
sweet or bitter oranges, is probably an error; for M. Alph. De Candolle
informs me that since the publication of his great work he has received
accounts from Guiana, the Antilles, and Mauritius, that in these
countries sweet oranges faithfully transmit their character. Gallesio
found that the willow-leafed and the Little China oranges reproduced
their proper leaves and fruit; but the seedlings were not quite equal
in merit to their parents. The red-fleshed orange, on the other hand,
fails to reproduce itself. Gallesio also observed that the seeds of
several other singular varieties all reproduced trees having a peculiar
physiognomy, but partly resembling their parent-forms. I can adduce
another case: the myrtle-leaved orange is ranked by all authors as a
variety, but is very distinct in general aspect: in my father's
greenhouse, during many years, it rarely yielded any seed, but at last
produced one; and a tree thus raised was identical with the
parent-form.
Another and more serious difficulty in determining the rank of the
several forms is that, according to Gallesio,[630] they largely
intercross without {336} artificial aid; thus he positively states that
seeds taken from lemon-trees (_C. lemonum_) growing mingled with the
citron (_C. medica_), which is generally considered as a distinct
species, produced a graduated series of varieties between these two
forms. Again, an Adam's apple was produced from the seed of a sweet
orange, which grew close to lemons and citrons. But such facts hardly
aid us in determining whether to rank these forms as species or
varieties; for it is now known that undoubted species of Verbascum,
Cistus, Primula, Salix, &c., frequently cross in a state of nature. If
indeed it were proved that plants of the orange tribe raised from these
crosses were even partially sterile, it would be a strong argument in
favour of their rank as species. Gallesio asserts that this is the
case; but he does not distinguish between sterility from hybridism and
from the effects of culture; and he almost destroys the force of this
statement by another,[631] namely, that when he impregnated the flowers
of the common orange with the pollen taken from undoubted _varieties_
of the orange, monstrous fruits were produced, which included "little
pulp, and had no seeds, or imperfect seeds."
In this tribe of plants we meet with instances of two highly remarkable
facts in vegetable physiology: Gallesio[632] impregnated an orange with
pollen from a lemon, and the fruit borne on the mother tree had a
raised stripe of peel like that of a lemon both in colour and taste,
but the pulp was like that of an orange and included only imperfect
seeds. The possibility of pollen from one variety or species directly
affecting the fruit produced by another variety or species, is a
subject which I shall fully discuss in the following chapter.
The second remarkable fact is that two supposed hybrids[633] (for their
hybrid nature was not ascertained) between an orange and either a lemon
or citron produced, on the same tree, leaves, flowers, and fruit of
both pure parent-forms, as well as of a mixed or crossed nature. A bud
taken from any one of the branches and grafted on another tree produces
either one of the pure kinds or a capricious tree reproducing the three
kinds. Whether the sweet lemon, which includes within the same fruit
segments of differently flavoured pulp,[634] is an analogous case, I
know not. But to this subject I shall have to recur.
I will conclude by giving from A. Risso[635] a short account of a very
singular variety of the common orange. It is the "_citrus aurantium
fructu variabili_," which on the young shoots produces rounded-oval
leaves spotted with yellow, borne on petioles with heart-shaped wings;
when these leaves fall off, they are succeeded by longer and narrower
leaves, with undulated margins, of a pale-green colour embroidered with
yellow, borne on foot-stalks without wings. The fruit whilst young is
pear-shaped, yellow, longitudinally striated, and sweet; but as it
ripens, it becomes spherical, of a reddish-yellow, and bitter.
_Peach and Nectarine (Amygdalus Persica)._ The best authorities are
{337} nearly unanimous that the peach has never been found wild. It was
introduced from Persia into Europe a little before the Christian era,
and at this period few varieties existed. Alph. De Candolle,[636] from
the fact of the peach not having spread from Persia at an earlier
period, and from its not having pure Sanscrit or Hebrew names, believes
that it is not an aboriginal of Western Asia, but came from the _terra
incognita_ of China. The supposition, however, that the peach is a
modified almond which acquired its present character at a comparatively
late period, would, I presume, account for these facts; on the same
principle that the nectarine, the offspring of the peach, has few
native names, and became known in Europe at a still later period.
[Illustration: Fig. 42.--Peach and Almond Stones, of natural size,
viewed edgeways. 1. Common English Peach. 2. Double, crimson-flowered,
Chinese Peach. 3. Chinese Honey Peach. 4. English Almond. 5. Barcelona
Almond. 6. Malaga Almond. 7. Soft-shelled French Almond. 8. Smyrna
Almond.]
{338}
Andrew Knight,[637] from finding that a seedling-tree, raised from a
sweet almond fertilised by the pollen of a peach, yielded fruit quite
like that of a peach, suspected that the peach-tree is a modified
almond; and in this he has been followed by various authors.[638] A
first-rate peach, almost globular in shape, formed of soft and sweet
pulp, surrounding a hard, much furrowed, and slightly-flattened stone,
certainly differs greatly from an almond, with its soft, slightly
furrowed, much flattened, and elongated stone, protected by a tough,
greenish layer of bitter flesh. Mr. Bentham[639] has particularly
called attention to the stone of the almond being so much more
flattened than that of the peach. But in the several varieties of the
almond, the stone differs greatly in the degree to which it is
compressed, in size, shape, strength, and in the depth of the furrows,
as may be seen in the accompanying drawings (Nos. 4 to 8) of such kinds
as I have been able to collect. With peach-stones, also (Nos. 1 to 3)
the degree of compression and elongation is seen to vary; so that the
stone of the Chinese Honey-peach (fig. 3) is much more elongated and
compressed than that of the (No. 8) Smyrna almond. Mr. Rivers of
Sawbridgeworth, to whom I am indebted for some of the specimens above
figured, and who has had such great horticultural experience, has
called my attention to several varieties which connect the almond and
the peach. In France there is a variety called the Peach-almond, which
Mr. Rivers formerly cultivated, and which is correctly described in a
French catalogue as being oval and swollen, with the aspect of a peach,
including a hard stone surrounded by a fleshy covering, which is
sometimes eatable.[640] A remarkable statement by M. Luizet has
recently appeared in the 'Revue Horticole,'[641] namely, that a
Peach-almond, grafted on a peach, bore during 1863 and 1864 almonds
alone, but in 1865 bore six peaches and no almonds. M. Carriere, in
commenting on this fact, cites the case of a double-flowered almond
which, after producing during several years almonds, suddenly bore for
two years in succession spherical fleshy peach-like fruits, but in 1865
reverted to its former state and produced large almonds.
Again, as I hear from Mr. Rivers, the double-flowering Chinese peaches
resemble almonds in their manner of growth and in their flowers; the
fruit is much elongated and flattened, with the flesh both bitter and
sweet, but {339} not uneatable, and it is said to be of better quality
in China. From this stage one small step leads us to such inferior
peaches as are occasionally raised from seed. For instance, Mr. Rivers
sowed a number of peach-stones imported from the United States, where
they are collected for raising stocks, and some of the trees raised by
him produced peaches which were very like almonds in appearance, being
small and hard, with the pulp not softening till very late in the
autumn. Van Mons[642] also states that he once raised from a
peach-stone a peach having the aspect of a wild tree, with fruit like
that of the almond. From inferior peaches, such as these just
described, we may pass by small transitions, through clingstones of
poor quality, to our best and most melting kinds. From this gradation,
from the cases of sudden variation above recorded, and from the fact
that the peach has not been found wild, it seems to me by far the most
probable view, that the peach is the descendant of the almond, improved
and modified in a marvellous manner.
One fact, however, is opposed to this conclusion. A hybrid, raised by
Knight from the sweet almond by the pollen of the peach, produced
flowers with little or no pollen, yet bore fruit, having been
apparently fertilised by a neighbouring nectarine. Another hybrid from
a sweet almond by the pollen of a nectarine produced during the first
three years imperfect blossoms, but afterwards perfect flowers with an
abundance of pollen. If this slight degree of sterility cannot be
accounted for by the youth of the trees (and this often causes lessened
fertility), or by the monstrous state of the flowers, or by the
conditions to which the trees were exposed, these two cases would
afford a strong argument against the peach being the descendant of the
almond.
Whether or not the peach has proceeded from the almond, it has
certainly given rise to nectarines, or smooth peaches, as they are
called by the French. Most of the varieties both of the peach and
nectarine reproduce themselves truly by seed. Gallesio[643] says he has
verified this with respect to eight races of the peach. Mr. Rivers[644]
has given some striking instances from his own experience, and it is
notorious that good peaches are constantly raised in North America from
seed. Many of the American sub-varieties come true or nearly true to
their kind, such as the white-blossom, several of the yellow-fruited
freestone peaches, the blood clingstone, the heath, and the
lemon-clingstone. On the other hand, a clingstone peach has been known
to give rise to a freestone.[645] In England it has been noticed that
seedlings inherit from their parents flowers of the same size and
colour. Some characters, however, contrary to what might have been
expected, often are not inherited; such as the presence and form of the
glands on the leaves.[646] With respect to nectarines, both cling and
{340} freestones are known in North America to reproduce themselves by
seed.[647] In England the new white nectarine was a seedling of the old
white, and Mr. Rivers[648] has recorded several similar cases. From
this strong tendency to inheritance, which both peach and nectarine
trees exhibit,--from certain slight constitutional differences[649] in
their nature,--and from the great difference in their fruit both in
appearance and flavour, it is not surprising, notwithstanding that the
trees differ in no other respects and cannot even be distinguished, as
I am informed by Mr. Rivers, whilst young, that they have been ranked
by some authors as specifically distinct. Gallesio does not doubt that
they are distinct; even Alph. De Candolle does not appear perfectly
assured of their specific identity; and an eminent botanist has quite
recently[650] maintained that the nectarine "probably constitutes a
distinct species."
Hence it may be worth while to give all the evidence on the origin of
the nectarine. The facts in themselves are curious, and will hereafter
have to be referred to when the important subject of bud-variation is
discussed. It is asserted[651] that the Boston nectarine was produced
from a peach-stone, and this nectarine reproduced itself by seed.[652]
Mr. Rivers states[653] that from stones of three distinct varieties of
the peach he raised three varieties of nectarine; and in one of these
cases no nectarine grew near the parent peach-tree. In another instance
Mr. Rivers raised a nectarine from a peach, and in the succeeding
generation another nectarine from this nectarine.[654] Other such
instances have been communicated to me, but they need not be given. Of
the converse case, namely, of nectarine-stones yielding peach-trees
(both free and cling-stones), we have six undoubted instances recorded
by Mr. Rivers; and in two of these instances the parent nectarines had
been seedlings from other nectarines.[655]
With respect to the more curious case of full-grown peach-trees
suddenly producing nectarines by bud-variation (or sports as they are
called by gardeners), the evidence is superabundant; there is also good
evidence of the same tree producing both peaches and nectarines, or
half and half fruit;--by this term I mean a fruit with the one-half a
perfect peach, and the other half a perfect nectarine.
Peter Collinson in 1741 recorded the first case of a peach-tree
producing a nectarine,[656] and in 1766 he added two other instances.
In the same work, the editor, Sir J. E. Smith, describes the more
remarkable case of a tree in Norfolk, which usually bore both perfect
nectarines and perfect peaches; but during two seasons some of the
fruit were half-and-half in nature.
{341} Mr. Salisbury in 1808[657] records six other cases of peach-trees
producing nectarines. Three of the varieties are named; viz., the
Alberge, Belle Chevreuse, and Royal George. This latter tree seldom
failed to produce both kinds of fruit. He gives another case of a
half-and-half fruit.
At Radford in Devonshire[658] a clingstone peach, purchased as the
Chancellor, was planted in 1815, and in 1824, after having previously
produced peaches alone, bore on one branch twelve nectarines; in 1825
the same branch yielded twenty-six nectarines, and in 1826 thirty-six
nectarines together with eighteen peaches. One of the peaches was
almost as smooth on one side as a nectarine. The nectarines were as
dark as, but smaller than, the Elruge.
At Beccles a Royal George peach[659] produced a fruit, "three parts of
it being peach and one part nectarine, quite distinct in appearance as
well as in flavour." The lines of division were longitudinal, as
represented in the engraving. A nectarine-tree grew five yards from
this tree.
Professor Chapman states[660] that he has often seen in Virginia very
old peach-trees bearing nectarines.
A writer in the 'Gardener's Chronicle' says that a peach-tree planted
fifteen years previously[661] produced this year a nectarine between
two peaches; a nectarine-tree grew close by.
In 1844[662] a Vanguard peach-tree produced, in the midst of its
ordinary fruit, a single red Roman nectarine.
Mr. Calver is stated[663] to have raised in the United States a
seedling peach which produced a mixed crop of both peaches and
nectarines.
Near Dorking[664] a branch of the Teton de Venus peach, which
reproduces itself truly by seed,[665] bore its own fruit "so remarkable
for its prominent point, and a nectarine rather smaller but well formed
and quite round."
The previous cases all refer to peaches suddenly producing nectarines,
but at Carclew[666] the unique case occurred, of a nectarine-tree,
raised twenty years before from seed and never grafted, producing a
fruit half peach and half nectarine; subsequently it bore a perfect
peach.
To sum up the foregoing facts: we have excellent evidence of
peach-stones producing nectarine-trees, and of nectarine-stones
producing peach-trees,--of the same tree bearing peaches and
nectarines,--of peach-trees suddenly producing by bud-variation
nectarines (such nectarines reproducing nectarines by seed), as well as
fruit in part nectarine and in part peach,--and lastly of one
nectarine-tree first bearing half-and-half fruit, and subsequently true
peaches. As the peach came into existence before the nectarine, it
might have been expected from the law of reversion that {342}
nectarines would give birth by bud-variation or by seed to peaches,
oftener than peaches to nectarines; but this is by no means the case.
Two explanations have been suggested to account for these conversions.
First, that the parent-trees have been in every case hybrids[667]
between the peach and nectarine, and have reverted by bud-variation or
by seed to one of their pure parent-forms. This view in itself is not
very improbable; for the Mountaineer peach, which was raised by Knight
from the red nutmeg peach by pollen of the violette hative
nectarine,[668] produces peaches, but these are said _sometimes_ to
partake of the smoothness and flavour of the nectarine. But let it be
observed that in the previous list no less than six well-known
varieties and several other unnamed varieties of the peach have once
suddenly produced perfect nectarines by bud-variation; and it would be
an extremely rash supposition that all these varieties of the peach,
which have been cultivated for years in many districts, and which show
not a vestige of a mixed parentage, are, nevertheless, hybrids. A
second explanation is, that the fruit of the peach has been directly
affected by the pollen of the nectarine: although this certainly is
possible, it cannot here apply; for we have not a shadow of evidence
that a branch which has borne fruit directly affected by foreign pollen
is so profoundly modified as afterwards to produce buds which continue
to yield fruit of the new and modified form. Now it is known that when
a bud on a peach-tree has once borne a nectarine the same branch has in
several instances gone on during successive years producing nectarines.
The Carclew nectarine, on the other hand, first produced half-and-half
fruit, and subsequently pure peaches. Hence we may confidently accept
the common view that the nectarine is a variety of the peach, which may
be produced either by bud-variation or from seed. In the following
chapter many analogous cases of bud-variation will be given.
The varieties of the peach and nectarine run in parallel lines. In both
classes the kinds differ from each other in the flesh of the fruit
being white, red, or yellow; in being clingstones or freestones; in the
flowers being large or small, with certain other characteristic
differences; and in the leaves being serrated without glands, or
crenated and furnished with globose or reniform glands.[669] We can
hardly account for this parallelism by supposing that each variety of
the nectarine is descended from a corresponding variety of the peach;
for though our nectarines are certainly the descendants of several
kinds of peaches, yet a large number are the descendants of other
nectarines, and they vary so much when thus reproduced that we can
scarcely admit the above explanation.
The varieties of the peach have largely increased in number since the
Christian era, when from two to five varieties alone were known;[670]
and the nectarine was unknown. At the present time, besides many
varieties said to exist in China, Downing describes in the United
States seventy-nine {343} native and imported varieties of the peach;
and a few years ago Lindley[671] enumerated one hundred and sixty-four
varieties of the peach and nectarine grown in England. I have already
indicated the chief points of difference between the several varieties.
Nectarines, even when produced from distinct kinds of peaches, always
possess their own peculiar flavour, and are smooth and small.
Clingstone and freestone peaches, which differ in the ripe flesh either
firmly adhering to the stone, or easily separating from it, also differ
in the character of the stone itself; that of the freestones or melters
being more deeply fissured, with the sides of the fissures smoother
than in clingstones. In the various kinds, the flowers differ not only
in size, but in the larger flowers the petals are differently shaped,
more imbricated, generally red in the centre and pale towards the
margin; whereas in the smaller flowers the margins of the petal are
usually more darkly coloured. One variety has nearly white flowers. The
leaves are more or less serrated, and are either destitute of glands,
or have globose or reniform glands;[672] and some few peaches, such as
the Brugnon, bear on the same tree both globular and kidney-shaped
glands.[673] According to Robertson[674] the trees with glandular
leaves are liable to blister, but not in any great degree to mildew;
whilst the non-glandular trees are more subject to curl, to mildew, and
to the attacks of aphides. The varieties differ in the period of their
maturity, in the fruit keeping well, and in hardiness,--the latter
circumstance being especially attended to in the United States. Certain
varieties, such as the Bellegarde, stand forcing in hot-houses better
than other varieties. The flat-peach of China is the most remarkable of
all the varieties; it is so much depressed towards the summit, that the
stone is here covered only by roughened skin and not by a fleshy
layer.[675] Another Chinese variety, called the Honey-peach, is
remarkable from the fruit terminating in a long sharp point; its leaves
are glandless and widely dentate.[676] The Emperor of Russia peach is a
third singular variety, having deeply and doubly serrated leaves; the
fruit is deeply cleft with one-half projecting considerably beyond the
other; it originated in America, and its seedlings inherit similar
leaves.[677]
The peach has also produced in China a small class of trees valued for
ornament, namely the double-flowered; of these five varieties are now
known in England, varying from pure white, through rose, to intense
crimson.[678] One of these varieties, called the camellia-flowered,
bears flowers above 21/4 inches in diameter, whilst those of the
fruit-bearing kinds do not at most exceed 11/4 inch in diameter. The
flowers of the {344} double-flowered peaches have the singular
property[679] of frequently producing double or treble fruit. Finally,
there is good reason to believe that the peach is an almond profoundly
modified; but whatever its origin may have been, there can be no doubt
that it has yielded during the last eighteen centuries many varieties,
some of them strongly characterised, belonging both to the nectarine
and peach form.
_Apricot_ (_Prunus armeniaca_).--It is commonly admitted that this tree
is descended from a single species, now found wild in the Caucasian
region.[680] On this view the varieties deserve notice, because they
illustrate differences supposed by some botanists to be of specific
value in the almond and plum. The best monograph on the apricot is by
Mr. Thompson,[681] who describes seventeen varieties. We have seen that
peaches and nectarines vary in a strictly parallel manner; and in the
apricot, which forms a closely allied genus, we again meet with
variations analogous to those of the peach, as well as to those of the
plum. The varieties differ considerably in the shape of their leaves,
which are either serrated or crenated, sometimes with ear-like
appendages at their bases, and sometimes with glands on the petioles.
The flowers are generally alike, but are small in the Masculine. The
fruit varies much in size, shape, and in having the suture little
pronounced or absent; in the skin being smooth, or downy as in the
orange-apricot; and in the flesh clinging to the stone, as in the
last-mentioned kind, or in readily separating from it, as in the
Turkey-apricot. In all these differences we see the closest analogy
with the varieties of the peach and nectarine. In the stone we have
more important differences, and these in the case of the plum have been
esteemed of specific value: in some apricots the stone is almost
spherical, in others much flattened, being either sharp in front or
blunt at both ends, sometimes channelled along the back, or with a
sharp ridge along both margins. In the Moorpark, and generally in the
Hemskirke, the stone presents a singular character in being perforated,
with a bundle of fibres passing through the perforation from end to
end. The most constant and important character, according to Thompson,
is whether the kernel is bitter or sweet; yet in this respect we have a
graduated difference, for the kernel is very bitter in Shipley's
apricot; in the Hemskirke less bitter than in some other kinds;
slightly bitter in the Royal; and "sweet like a hazel-nut" in the
Breda, Angoumois, and others. In the case of the almond, bitterness has
been thought by some high authorities to indicate specific difference.
In N. America the Roman apricot endures "cold and unfavourable
situations, where no other sort, except the Masculine, will succeed;
and its blossoms bear quite a severe frost without injury."[682]
According to Mr. Rivers[683] seedling apricots deviate but little from
the character of {345} their race: in France the Alberge is constantly
reproduced from seed with but little variation. In Ladakh, according to
Moorcroft,[684] ten varieties of the apricot, very different from each
other, are cultivated, and all are raised from seed, excepting one,
which is budded.
[Illustration: Fig. 43.--Plum Stones, of natural size, viewed
laterally. 1. Bullace Plum. 2. Shropshire Damson. 3. Blue Gage. 4.
Orleans. 5. Elvas. 6. Denyer's Victoria. 7. Diamond.]
_Plums_ (_Prunus insititia_).--Formerly the sloe, _P. spinosa_, was
thought to be the parent of all our plums; but now this honour is very
commonly accorded to _P. insititia_ or the bullace, which is found wild
in the Caucasus and N.-Western India, and is naturalised in
England.[685] It is not at all improbable, in accordance with some
observations made by Mr. Rivers[686] that both these forms, which some
botanists rank as a single species, may be the parents of our
domesticated plums. Another supposed parent-form, the _P. domestica_,
is said to be found wild in the region of the Caucasus. Godron
remarks[687] that the cultivated varieties may be divided into two main
groups, which he supposes to be descended from two aboriginal stocks;
namely, those with oblong fruit and stones pointed at both ends, having
narrow separate petals and upright branches; and those with rounded
fruit, with stones blunt at both ends, with rounded petals and
spreading branches. From what we know of the variability of the flowers
in the peach and of the diversified manner of growth in our various
fruit-trees, it is difficult to lay much weight on these latter {346}
characters. With respect to the shape of the fruit, we have conclusive
evidence that it is extremely variable: Downing[688] gives outlines of
the plums of two seedlings, namely, the red and imperial gages, raised
from the greengage; and the fruit of both is more elongated than that
of the greengage. The latter has a very blunt broad stone, whereas the
stone of the imperial gage is "oval and pointed at both ends." These
trees also differ in their manner of growth: "the greengage is a very
short-jointed, slow-growing tree, of spreading and rather dwarfish
habit;" whilst its offspring, the imperial gage, "grows freely and
rises rapidly, and has long dark shoots." The famous Washington plum
bears a globular fruit, but its offspring, the emerald drop, is nearly
as much elongated as the most elongated plum figured by Downing,
namely, Manning's prune. I have made a small collection of the stones
of twenty-five kinds, and they graduate in shape from the bluntest into
the sharpest kinds. As characters derived from seeds are generally of
high systematic importance, I have thought it worth while to give
drawings of the most distinct kinds in my small collection; and they
may be seen to differ in a surprising manner in size, outline,
thickness, prominence of the ridges, and state of surface. It deserves
notice that the shape of the stone is not always strictly correlated
with that of the fruit: thus the Washington plum is spherical and
depressed at the pole, with a somewhat elongated stone, whilst the
fruit of the Goliath is more elongated, but the stone less so, than in
the Washington. Again, Denyer's Victoria and Goliath bear fruit closely
resembling each other, but their stones are widely different. On the
other hand, the Harvest and Black Margate plums are very dissimilar,
yet include closely similar stones.
The varieties of the plum are numerous, and differ greatly in size,
shape, quality, and colour,--being bright yellow, green, almost white,
blue, purple, or red. There are some curious varieties, such as the
double or Siamese, and the Stoneless plum: in the latter the kernel
lies in a roomy cavity surrounded only by the pulp. The climate of
North America appears to be singularly favourable for the production of
new and good varieties; Downing describes no less than forty, seven of
which of first-rate quality have been recently introduced into
England.[689] Varieties occasionally arise having an innate adaptation
for certain soils, almost as strongly pronounced as with natural
species growing on the most distinct geological formations; thus in
America the imperial gage, differently from almost all other kinds, "is
peculiarly fitted for _dry light_ soils where many sorts drop their
fruit," whereas on rich heavy soils the fruit is often insipid.[690] My
father could never succeed in making the Wine-Sour yield even a
moderate crop in a sandy orchard near Shrewsbury, whilst in some parts
of the same county and in its native Yorkshire it bears abundantly: one
of my {347} relations also repeatedly tried in vain to grow this
variety in a sandy district in Staffordshire.
Mr. Rivers has given[691] a number of interesting facts, showing how
truly many varieties can be propagated by seed. He sowed the stones of
twenty bushels of the greengage for the sake of raising stocks, and
closely observed the seedlings; "all had the smooth shoots, the
prominent buds, and the glossy leaves of the greengage, but the greater
number had smaller leaves and thorns." There are two kinds of damson,
one the Shropshire with downy shoots, and the other the Kentish with
smooth shoots, and these differ but slightly in any other respect: Mr.
Rivers sowed some bushels of the Kentish damson, and all the
seedlings-had smooth shoots, but in some the fruit was oval, in others
round or roundish, and in a few the fruit was small, and, except in
being sweet, closely resembled that of the wild sloe. Mr. Rivers gives
several other striking instances of inheritance: thus, he raised eighty
thousand seedlings from the common German Quetsche plum, and "not one
could be found varying in the least, in foliage or habit." Similar
facts were observed with the Petite Mirabelle plum, yet this latter
kind (as well as the Quetsche) is known to have yielded some
well-established varieties; but, as Mr. Rivers remarks, they all belong
to the same group with the Mirabelle.
_Cherries (Prunus cerasus, avium_, &c.).--Botanists believe that our
cultivated cherries are descended from one, two, four, or even more
wild stocks.[692] That there must be at least two parent-species we may
infer from the sterility of twenty hybrids raised by Mr. Knight from
the morello fertilized by pollen of the Elton cherry; for these hybrids
produced in all only five cherries, and one alone of these contained a
seed.[693] Mr. Thompson[694] has classified the varieties in an
apparently natural method in two main groups by characters taken from
the flowers, fruit, and leaves; but some varieties which stand widely
separate in this classification are quite fertile when crossed; thus
Knight's Early Black cherry is the product of a cross between two such
kinds.
Mr. Knight states that seedling cherries are more variable than those
of any other fruit-tree.[695] In the Catalogue of the Horticultural
Society for 1842, eighty varieties are enumerated. Some varieties
present singular characters: thus the flower of the Cluster cherry
includes as many as twelve pistils, of which the majority abort; and
they are said generally to produce from two to five or six cherries
aggregated together and borne on a single peduncle. In the Ratafia
cherry several flower-peduncles arise from a common peduncle, upwards
of an inch in length. The fruit of Gascoigne's Heart has its apex
produced into a globule or drop: that of the white {348} Hungarian Gean
has almost transparent flesh. The Flemish cherry is "a very odd-looking
fruit," much flattened at the summit and base, with the latter deeply
furrowed, and borne on a stout very short footstalk. In the Kentish
cherry the stone adheres so firmly to the footstalk, that it can be
drawn out of the flesh; and this renders the fruit well fitted for
drying. The Tobacco-leaved cherry, according to Sageret and Thompson,
produces gigantic leaves, more than a foot and sometimes even eighteen
inches in length, and half a foot in breadth. The Weeping cherry, on
the other hand, is valuable only as an ornament, and, according to
Downing, is "a charming little tree with slender weeping branches,
clothed with small almost myrtle-like foliage." There is also a
peach-leaved variety.
Sageret describes a remarkable variety, _le griottier de la Toussaint_,
which bears at the same time, even as late as September, flowers and
fruit of all degrees of maturity. The fruit, which is of inferior
quality, is borne on long, very thin footstalks. But the extraordinary
statement is made that all the leaf-bearing shoots spring from old
flower-buds. Lastly, there is an important physiological distinction
between those kinds of cherries which bear fruit on young or on old
wood; but Sageret positively asserts that a Bigarreau in his garden
bore fruit on wood of both ages.[696]
_Apple (Pyrus malus)._--The one source of doubt felt by botanists with
respect to the parentage of the apple is whether, besides _P. malus_,
two or three other closely allied wild forms, namely, _P. acerba_ and
_praecox_ or _paradisiaca_, do not deserve to be ranked as distinct
species. The _P. praecox_ is supposed by some authors[697] to be the
parent of the dwarf paradise stock, which, owing to the fibrous roots
not penetrating deeply into the ground, is so largely used for
grafting; but the paradise stock, it is asserted,[698] cannot be
propagated true by seed. The common wild crab varies considerably in
England; but many of the varieties are believed to be escaped
seedlings.[699] Every one knows the great difference in the manner of
growth, in the foliage, flowers, and especially in the fruit, between
the almost innumerable varieties of the apple. The pips or seeds (as I
know by comparison) likewise differ considerably in shape, size, and
colour. The fruit is adapted for eating or for cooking in different
ways, and keeps for only a few weeks or for nearly two years. Some few
kinds have the fruit covered with a powdery secretion, called bloom,
like that on plums; {349} and "it is extremely remarkable that this
occurs almost exclusively among varieties cultivated in Russia."[700]
Another Russian apple, the white Astracan, possesses the singular
property of becoming transparent, when ripe, like some sorts of crabs.
The _api etoile_ has five prominent ridges, hence its name; the _api
noir_ is nearly black: the _twin cluster pippin_ often bears fruit
joined in pairs.[701] The trees of the several sorts differ greatly in
their periods of leafing and flowering; in my orchard the _Court Pendu
Plat_ produces its leaves so late, that during several springs I have
thought it dead. The Tiffin apple scarcely bears a leaf when in full
bloom; the Cornish crab, on the other hand, bears so many leaves at
this period that the flowers can hardly be seen.[702] In some kinds the
fruit ripens in midsummer; in others, late in the autumn. These several
differences in leafing, flowering, and fruiting, are not at all
necessarily correlated; for, as Andrew Knight has remarked,[703] no one
can judge from the early flowering of a new seedling, or from the early
shedding or change of colour of the leaves, whether it will mature its
fruit early in the season.
The varieties differ greatly in constitution. It is notorious that our
summers are not hot enough for the Newtown Pippin,[704] which is the
glory of the orchards near New York; and so it is with several
varieties which we have imported from the Continent. On the other hand,
our Court of Wick succeeds well under the severe climate of Canada. The
_Calville rouge de Micoud_ occasionally bears two crops during the same
year. The Burr Knot is covered with small excrescences, which emit
roots so readily that a branch with blossom-buds may be stuck in the
ground, and will root and bear a few fruit even during the first
year.[705] Mr. Rivers has recently described[706] some seedlings
valuable from their roots running near the surface. One of these
seedlings was remarkable from its extremely dwarfed size, "forming
itself into a bush only a few inches in height." Many varieties are
particularly liable to canker in certain soils. But perhaps the
strangest constitutional peculiarity is that the Winter Majetin is not
attacked by the mealy bug or coccus; Lindley[707] states that in an
orchard in Norfolk infested with these insects the Majetin was quite
free, though the stock on which it was grafted was affected: Knight
makes a similar statement with respect to a cider apple, and adds that
he only once saw these insects just above the stock, but that three
days afterwards they entirely disappeared; this apple, however, was
raised from a cross between {350} the Golden Harvey and the Siberian
Crab; and the latter, I believe, is considered by some authors as
specifically distinct.
The famous St. Valery apple must not be passed over; the flower has a
double calyx with ten divisions, and fourteen styles surmounted by
conspicuous oblique stigmas, but is destitute of stamens or corolla.
The fruit is constricted round the middle, and is formed of five
seed-cells, surmounted by nine other cells.[708] Not being provided
with stamens, the tree requires artificial fertilisation; and the girls
of St. Valery annually go to "_faire ses pommes_," each marking her own
fruit with a ribbon; and as different pollen is used, the fruit
differs, and we here have an instance of the direct action of foreign
pollen on the mother-plant. These monstrous apples include, as we have
seen, fourteen seed-cells; the pigeon-apple,[709] on the other hand,
has only four, instead of, as with all common apples, five cells; and
this certainly is a remarkable difference.
In the catalogue of apples published in 1842 by the Horticultural
Society, 897 varieties are enumerated; but the differences between most
of them are of comparatively little interest, as they are not strictly
inherited. No one can raise, for instance, from the seed of the Ribston
Pippin, a tree of the same kind; and it is said that the "Sister
Ribston Pippin" was a white, semi-transparent, sour-fleshed apple, or
rather large crab.[710] Yet it is a mistake to suppose that with most
varieties the characters are not to a certain extent inherited. In two
lots of seedlings raised from two well-marked kinds, many worthless,
crab-like seedlings will appear, but it is now known that the two lots
not only usually differ from each other, but resemble to a certain
extent their parents. We see this indeed in the several sub-groups of
Russetts, Sweetings, Codlins, Pearmains, Reinettes, &c.,[711] which are
all believed, and many are known, to be descended from other varieties
bearing the same names.
_Pears (Pyrus communis)._--I need say little on this fruit, which
varies much in the wild state, and to an extraordinary degree when
cultivated, in its fruit, flowers, and foliage. One of the most
celebrated botanists in Europe, M. Decaisne, has carefully studied the
many varieties;[712] although he formerly believed that they were
derived from more than one species, he is now convinced that all belong
to one. He has arrived at this conclusion from finding in the several
varieties a perfect gradation between the most extreme characters; so
perfect is this gradation that he maintains it to be impossible to
classify the varieties by any natural method. M. Decaisne raised many
seedlings from four distinct kinds, and has carefully recorded the
variations in each. Notwithstanding this extreme degree of {351}
variability, it is now positively known that many kinds reproduce by
seed the leading characters of their race.[713]
_Strawberries (Fragaria)._--This fruit is remarkable, on account of the
number of species which have been cultivated, and from their rapid
improvement within the last fifty or sixty years. Let any one compare
the fruit of one of the largest varieties exhibited at our Shows with
that of the wild wood strawberry, or, which will be a fairer
comparison, with the somewhat larger fruit of the wild American
Virginian Strawberry, and he will see what prodigies horticulture has
effected.[714] The number of varieties has likewise increased in a
surprisingly rapid manner. Only three kinds were known in France, in
1746, where this fruit was early cultivated. In 1766 five species had
been introduced, the same which are now cultivated, but only five
varieties of _Fragaria vesca_, with some sub-varieties, had been
produced. At the present day the varieties of the several species are
almost innumerable. The species consist of, firstly, the wood or Alpine
cultivated strawberries, descended from _F. vesca_, a native of Europe
and of North America. There are eight wild European varieties, as
ranked by Duchesne, of _F. vesca_, but several of these are considered
species by some botanists. Secondly, the green strawberries, descended
from the European _F. collina_, and little cultivated in England.
Thirdly, the Hautbois, from the European _F. elatior_. Fourthly, the
Scarlets, descended from _F. Virginiana_, a native of the whole breadth
of North America. Fifthly, the Chili, descended from _F. Chiloensis_,
an inhabitant of the west coast of the temperate parts both of North
and South America. Lastly, the Pines or Carolinas (including the old
Blacks), which have been ranked by most authors under the name of _F.
grandiflora_ as a distinct species, said to inhabit Surinam; but this
is a manifest error. This form is considered by the highest authority,
M. Gay, to be merely a strongly marked race of _F. Chiloensis_.[715]
These five or six forms have been ranked by most botanists as
specifically distinct; but this may be doubted, for Andrew Knight,[716]
who raised no less than 400 crossed strawberries, asserts that the _F.
Virginiana_, _Chiloensis_, and _grandiflora_ "may be made to breed
together indiscriminately," and he found, in accordance with the
principle of analogous variation, "that similar varieties could be
obtained from the seeds of any one of them."
Since Knight's time there is abundant and additional evidence[717] of
the extent to which the American forms spontaneously cross. We owe
{352} indeed to such crosses most of our choicest existing varieties.
Knight did not succeed in crossing the European wood-strawberry with
the American Scarlet or with the Hautbois. Mr. Williams, of Pitmaston,
however, succeeded; but the hybrid offspring from the Hautbois, though
fruiting well, never produced seed, with the exception of a single one,
which reproduced the parent hybrid form.[718] Major E. Trevor Clarke
informs me that he crossed two members of the Pine class (Myatt's B.
Queen and Keen's Seedling), with the wood and hautbois, and that in
each case he raised only a single seedling; one of these fruited, but
was almost barren. Mr. W. Smith, of York, has raised similar hybrids
with equally poor success.[719] We thus see[720] that the European and
American species can with some difficulty be crossed; but it is
improbable that hybrids sufficiently fertile to be worth cultivation
will ever be thus produced. This fact is surprising, as these forms
structurally are not widely distinct, and are sometimes connected in
the districts where they grow wild, as I hear from Professor Asa Gray,
by puzzling intermediate forms.
The energetic culture of the strawberry is of recent date, and the
cultivated varieties can in most cases still be classed under some one
of the above five native stocks. As the American strawberries cross so
freely and spontaneously, we can hardly doubt that they will ultimately
become inextricably confused. We find, indeed, that horticulturists at
present disagree under which class to rank some few of the varieties;
and a writer in the 'Bon Jardinier' of 1840 remarks that formerly it
was possible to class all of them under some one species, but that now
this is quite impossible with the American forms, the new English
varieties having completely filled up the gaps between them.[721] The
blending together of two or more aboriginal forms, which there is every
reason to believe has occurred with some of our anciently cultivated
productions, we now see actually occurring with our strawberries.
The cultivated species offer some variations worth notice. The Black
Prince, a seedling from Keen's Imperial (this latter being a seedling
of a very white strawberry, the white Carolina), is remarkable from
"its peculiar dark and polished surface, and from presenting an
appearance entirely unlike that of any other kind."[722] Although the
fruit in the different varieties differs so greatly in form, size,
colour, and quality, the so-called seed (which corresponds with the
whole fruit in the plum), with the exception of being more or less
deeply embedded in the pulp, is, according to De Jonghe,[723]
absolutely the same in all; and this no doubt may be accounted for by
the seed being of no value, and consequently not having been subjected
to selection. The strawberry is properly three-leaved, but in 1761
Duchesne raised a single-leaved variety of the European {353}
wood-strawberry, which Linnaeus doubtfully raised to the rank of a
species. Seedlings of this variety, like those of most varieties not
fixed by long-continued selection, often revert to the ordinary form,
or present intermediate states.[724] A variety raised by Mr.
Myatt,[725] apparently belonging to one of the American forms, presents
a variation of an opposite nature, for it has five leaves; Godron and
Lambertye also mention a five-leaved variety of _F. collina_.
The Red Bush Alpine strawberry (one of the _F. vesca_ section) does not
produce stolons or runners, and this remarkable deviation of structure
is reproduced truly by seed. Another sub-variety, the White Bush
Alpine, is similarly characterised, but when propagated by seed it
often degenerates and produces plants with runners.[726] A strawberry
of the American Pine section is also said to make but few runners.[727]
Much has been written on the sexes of strawberries; the true Hautbois
properly bears the male and female organs on separate plants,[728] and
was consequently named by Duchesne _dioica_; but it frequently produces
hermaphrodites; and Lindley,[729] by propagating such plants by
runners, at the same time destroying the males, soon raised a
self-prolific stock. The other species often show a tendency towards an
imperfect separation of the sexes, as I have noticed with plants forced
in a hot-house. Several English varieties, which in this country are
free from any such tendency, when cultivated in rich soils under the
climate of North America[730] commonly produce plants with separate
sexes. Thus a whole acre of Keen's Seedlings in the United States has
been observed to be almost sterile from the absence of male flowers;
but the more general rule is, that the male plants overrun the females.
Some members of the Cincinnati Horticultural Society, especially
appointed to investigate this subject, report that "few varieties have
the flowers perfect in both sexual organs," &c. The most successful
cultivators in Ohio, plant for every seven rows of "pistillata," or
female plants, one row of hermaphrodites, which afford pollen for both
kinds; but the hermaphrodites, owing to their expenditure in the
production of pollen, bear less fruit than the female plants.
The varieties differ in constitution. Some of our best English kinds,
such as Keen's Seedlings, are too tender for certain parts of North
America, where other English and many American varieties succeed
perfectly. That splendid fruit, the British Queen, can be cultivated
but in few places either in England or France; but this apparently
depends more on the nature of the soil than on the climate: a famous
gardener says that "no mortal could grow the British Queen at Shrubland
Park unless the whole nature of the soil was altered."[731] La
Constantina is one of the {354} hardiest kinds, and can withstand
Russian winters, but is easily burnt by the sun, so that it will not
succeed in certain soils either in England or the United States.[732]
The Filbert Pine Strawberry "requires more water than any other
variety; and if the plants once suffer from drought, they will do
little or no good afterwards."[733] Cuthill's Black Prince Strawberry
evinces a singular tendency to mildew: no less than six cases have been
recorded of this variety suffering severely, whilst other varieties
growing close by, and treated in exactly the same manner, were not at
all infested by this fungus.[734] The time of maturity differs much in
the different varieties; some belonging to the wood or alpine section
produce a succession of crops throughout the summer.
_Gooseberry_ (_Ribes grossularia_).--No one, I believe, has hitherto
doubted that all the cultivated kinds are sprung from the wild plant
bearing this name, which is common in Central and Northern Europe;
therefore it will be desirable briefly to specify all the points,
though not very important, which have varied. If it be admitted that
these differences are due to culture, authors perhaps will not be so
ready to assume the existence of a large number of unknown wild
parent-stocks for our other cultivated plants. The gooseberry is not
alluded to by writers of the classical period. Turner mentions it in
1573, and Parkinson, in 1629, specifies eight varieties; the Catalogue
of the Horticultural Society for 1842 gives 149 varieties, and the
lists of the Lancashire nurserymen are said to include above 300
names.[735] In the 'Gooseberry Grower's Register for 1862' I find that
243 distinct varieties have at various periods won prizes; so that a
vast number must have been exhibited. No doubt the difference between
many of the varieties is very small; but Mr. Thompson in classifying
the fruit for the Horticultural Society found less confusion in the
nomenclature of the gooseberry than of any other fruit, and he
attributes this "to the great interest which the prize-growers have
taken in detecting sorts with wrong names," and this shows that all the
kinds, numerous as they are, can be recognised with certainty.
The bushes differ in their manner of growth, being erect, or spreading,
or pendulous. The periods of leafing and flowering differ both
absolutely and relatively to each other; thus the Whitesmith produces
early flowers, which from not being protected by the foliage, as it is
believed, continually fail to produce fruit.[736] The leaves vary in
size, tint, and in depth of lobes; they are smooth, downy, or hairy on
the upper surface. The branches are more or less downy or spinose; "the
Hedgehog has probably derived its name from the singular bristly
condition of its shoots and fruit." The branches of the wild
gooseberry, I may remark, are smooth, with the exception of thorns at
the bases of the buds. The thorns themselves are either very small, few
and single, or very large and triple; they are {355} sometimes reflexed
and much dilated at their bases. In the different varieties the fruit
varies in abundance, in the period of maturity, in hanging until
shrivelled, and greatly in size, "some sorts having their fruit large
during a very early period of growth, whilst others are small until
nearly ripe." The fruit varies also much in colour, being red, yellow,
green, and white--the pulp of one dark-red gooseberry being tinged with
yellow; in flavour; in being smooth or downy,--few, however, of the Red
gooseberries, whilst many of the so-called Whites, are downy; or in
being so spinose that one kind is called Henderson's Porcupine. Two
kinds acquire when mature a powdery bloom on their fruit. The fruit
varies in the thickness and veining of the skin, and, lastly, in shape,
being spherical, oblong, oval, or obovate.[737]
I cultivated fifty-four varieties, and, considering how greatly the
fruit differs, it was curious how closely similar the flowers were in
all these kinds. In only a few I detected a trace of difference in the
size or colour of the corolla. The calyx differed in a rather greater
degree, for in some kinds it was much redder than in others; and in one
smooth white gooseberry it was unusually red. The calyx also differed
in the basal part being smooth or woolly, or covered with glandular
hairs. It deserves notice, as being contrary to what might have been
expected from the law of correlation, that a smooth red gooseberry had
a remarkably hairy calyx. The flowers of the Sportsman are furnished
with very large coloured bracteae; and this is the most singular
deviation of structure which I have observed. These same flowers also
varied much in the number of the petals, and occasionally in the number
of the stamens and pistils; so that they were semi-monstrous in
structure, yet they produced plenty of fruit. Mr. Thompson remarks that
in the Pastime gooseberry "extra bracts are often attached to the sides
of the fruit."[738]
The most interesting point in the history of the gooseberry is the
steady increase in the size of the fruit. Manchester is the metropolis
of the fanciers, and prizes from five shillings to five or ten pounds
are yearly given for the heaviest fruit. The 'Gooseberry Grower's
Register' is published annually; the earliest known copy is dated 1786,
but it is certain that meetings for the adjudication of prizes were
held some years previously.[739] The 'Register' for 1845 gives an
account of 171 Gooseberry Shows, held in different places during that
year; and this fact shows on how large a scale the culture has been
carried on. The fruit of the wild gooseberry is said[740] to weigh
about a quarter of an ounce or 5 dwts., that is, 120 grains; about the
year 1786 gooseberries were exhibited weighing 10 dwts., so that the
weight was then doubled; in 1817 26 dwts. 17 grs. was attained; there
was no advance till 1825, when 31 dwts. 16 grs. was reached; in {356}
1830 "Teazer" weighed 32 dwts. 13 grs.; in 1841 "Wonderful" weighed 32
dwts. 16 grs.; in 1844 "London" weighed 35 dwts. 12 grs., and in the
following year 36 dwts. 16 grs.; and in 1852 in Staffordshire the fruit
of this same variety reached the astonishing weight of 37 dwts. 7
grs.,[741] or 895 grs.; that is, between seven and eight times the
weight of the wild fruit. I find that a small apple, 61/2 inches in
circumference, has exactly this same weight. The "London" gooseberry
(which in 1862 had altogether gained 343 prizes) has, up to the present
year of 1864, never reached a greater weight than that attained in
1852. Perhaps the fruit of the gooseberry has now reached the greatest
possible weight, unless in the course of time some quite new and
distinct variety shall arise.
This gradual, and on the whole steady increase of weight from the
latter part of the last century to the year 1852, is probably in large
part due to improved methods of cultivation, for extreme care is now
taken; the branches and roots are trained, composts are made, the soil
is mulched, and only a few berries are left on each bush;[742] but the
increase no doubt is in main part due to the continued selection of
seedlings which have been found to be more and more capable of yielding
such extraordinary fruit. Assuredly the "Highwayman" in 1817 could not
have produced fruit like that of the "Roaring Lion" in 1825; nor could
the "Roaring Lion," though it was grown by many persons in many places,
gain the supreme triumph achieved in 1852 by the "London" Gooseberry.
_Walnut_ (_Juglans regia_).--This tree and the common nut belong to a
widely different order from the foregoing fruits, and are therefore
here noticed. The walnut grows wild in the Caucasus and Himalaya, where
Dr. Hooker[743] found the fruit of full size, but "as hard as a
hickory-nut." In England the walnut presents considerable differences,
in the shape and size of the fruit, in the thickness of the husk, and
in the thinness of the shell; this latter quality has given rise to a
variety called the thin-shelled, which is valuable, but suffers from
the attacks of tom-tits.[744] The degree to which the kernel fills the
shell varies much. In France there is a variety called the Grape or
cluster-walnut, in which the nuts grow in "bunches of ten, fifteen, or
even twenty together." There is another variety which bears on the same
tree differently shaped leaves, like the heterophyllous hornbeam; this
tree is also remarkable from having pendulous branches, and bearing
elongated, large, thin-shelled nuts.[745] M. Cardan has minutely
described[746] some singular physiological peculiarities in the
June-leafing variety, which produces its leaves and flowers four or
five weeks later, and retains its leaves and fruit in the autumn much
longer, than the common varieties; {357} but in August is in exactly
the same state with them. These constitutional peculiarities are
strictly inherited. Lastly, walnut-trees, which are properly monoicous,
sometimes entirely fail to produce male flowers.[747]
_Nuts_ (_Corylus avellana_).--Most botanists rank all the varieties
under the same species, the common wild nut.[748] The husk, or
involucre, differs greatly, being extremely short in Barr's Spanish,
and extremely long in filberts, in which it is contracted so as to
prevent the nut falling out. This kind of husk also protects the nut
from birds, for titmice (_Parus_) have been observed[749] to pass over
filberts, and attack cobs and common nuts growing in the same orchard.
In the purple-filbert the husk is purple, and in the frizzled-filbert
it is curiously laciniated; in the red-filbert the pellicle of the
kernel is red. The shell is thick in some varieties, but is thin in
Cosford's-nut, and in one variety is of a bluish colour. The nut itself
differs much in size and shape, being ovate and compressed in filberts,
nearly round and of great size in cobs and Spanish nuts, oblong and
longitudinally striated in Cosford's, and obtusely four-sided in the
Downton Square nut.
_Cucurbitaceous plants._--These plants have been for a long period the
opprobrium of botanists; numerous varieties have been ranked as
species, and, what happens more rarely, forms which now must be
considered as species have been classed as varieties. Owing to the
admirable experimental researches of a distinguished botanist, M.
Naudin,[750] a flood of light has recently been thrown on this group of
plants. M. Naudin, during many years, observed and experimented on
above 1200 living specimens, collected from all quarters of the world.
Six species are now recognised in the genus Cucurbita; but three alone
have been cultivated and concern us, namely, _C. maxima_ and _pepo_,
which include all pumpkins, gourds, squashes, and vegetable marrow, and
_C. moschata_, the water-melon. These three species are not known in a
wild state; but Asa Gray[751] gives good reason for believing that some
pumpkins are natives of N. America.
These three species are closely allied, and have the same general
habit, but their innumerable varieties can always be distinguished,
according to Naudin, by certain almost fixed characters; and what is
still more important, when crossed they yield no seed, or only sterile
seed; whilst the varieties spontaneously intercross with the utmost
freedom. Naudin insists strongly (p. 15), that, though these three
species have varied greatly in many characters, yet it has been in so
closely an analogous manner that the varieties can be arranged in
almost parallel series, as we have seen with the forms of wheat, with
the two main races of the peach, and in other cases. Though some of the
varieties are inconstant in character, yet others, when grown
separately under uniform conditions of life, are, as Naudin repeatedly
(pp. 6, 16, 35) urges, "douees d'une stabilite {358} presque comparable
a celle des especes les mieux caracterisees." One variety, l'Orangin
(pp. 43, 63), has such prepotency in transmitting its character that
when crossed with other varieties a vast majority of the seedlings come
true. Naudin, referring (p. 47) to _C. pepo_, says that its races "ne
different des especes veritables qu'en ce qu'elles peuvent s'allier les
unes aux autres par voie d'hybridite, sans que leur descendance perde
la faculte de se perpetuer." If we were to trust to external
differences alone, and give up the test of sterility, a multitude of
species would have to be formed out of the varieties of these three
species of Cucurbita. Many naturalists at the present day lay far too
little stress, in my opinion, on the test of sterility; yet it is not
improbable that distinct species of plants after a long course of
cultivation and variation may have their mutual sterility eliminated,
as we have every reason to believe has occurred with domesticated
animals. Nor, in the case of plants under cultivation, should we be
justified in assuming that varieties never acquire a slight degree of
mutual sterility, as we shall more fully see in a future chapter when
certain facts are given on the high authority of Gaertner and
Koelreuter.[752]
The forms of _C. pepo_ are classed by Naudin under seven sections, each
including subordinate varieties. He considers this plant as probably
the most variable in the world. The fruit of one variety (pp. 33, 46)
exceeds in volume that of another by more than two thousand fold! When
the fruit is of very large size, the number produced is few (p. 45);
when of small size, many are produced. No less astonishing (p. 33) is
the variation in the shape of the fruit; the typical form apparently is
egg-like, but this becomes either drawn out into a cylinder, or
shortened into a flat disc. We have also an almost infinite diversity
in the colour and state of surface of the fruit, in the hardness both
of the shell and of the flesh, and in the taste of the flesh, which is
either extremely sweet, farinaceous, or slightly bitter. The seeds also
differ in a slight degree in shape, and wonderfully in size (p. 34),
namely, from six or seven to more than twenty-five millimetres in
length.
In the varieties which grow upright or do not run and climb, the
tendrils, though useless (p. 31), are either present or are represented
by various semi-monstrous organs, or are quite absent. The tendrils are
even absent in some running varieties in which the stems are much
elongated. It is a singular fact that (p. 31), in all the varieties
with dwarfed stems, the leaves closely resemble each other in shape.
Those naturalists who believe in the immutability of species often
maintain that, even in the most variable forms, the characters which
they consider of specific value are unchangeable. To give an example
from a conscientious writer,[753] who, relying on the labours of M.
Naudin and {359} referring to the species of Cucurbita, says, "au
milieu de toutes les variations du fruit, les tiges, les feuilles, les
calices, les corolles, les etamines restent invariables dans chacune
d'elles." Yet M. Naudin in describing _Cucurbita pepo_ (p. 30) says,
"Ici, d'ailleurs, ce ne sont pas seulement les fruits qui varient,
c'est aussi le feuillage et tout le port de la plante. Neanmoins, je
crois qu'on la distinguera toujours facilement des deux autres especes,
si l'on veut ne pas perdre de vue les caracteres differentiels que je
m'efforce de faire ressortir. Ces caracteres sont quelquefois peu
marques: il arrive meme que plusieurs d'entre eux s'effacent presque
entierement, mais il en reste toujours quelques-uns qui remettent
l'observateur sur la voie." Now let it be noted what a difference, with
regard to the immutability of the so-called specific characters, this
paragraph produces on the mind, from that above quoted from M. Godron.
I will add another remark: naturalists continually assert that no
important organ varies; but in saying this they unconsciously argue in
a vicious circle; for if an organ, let it be what it may, is highly
variable, it is regarded as unimportant, and under a systematic point
of view this is quite correct. But as long as constancy is thus taken
as the criterion of importance, it will indeed be long before an
important organ can be shown to be inconstant. The enlarged form of the
stigmas, and their sessile position on the summit of the ovary, must be
considered as important characters, and were used by Gasparini to
separate certain pumpkins as a _distinct genus_; but Naudin says (p.
20) these parts have no constancy, and in the flowers of the Turban
varieties of _C. maxima_ they sometimes resume their ordinary
structure. Again, in _C. maxima_, the carpels (p. 19) which form the
Turban project even as much as two-thirds of their length out of the
receptacle, and this latter part is thus reduced to a sort of platform;
but this remarkable structure occurs only in certain varieties, and
graduates into the common form in which the carpels are almost entirely
enveloped within the receptacle. In _C. moschata_ the ovarium (p. 50)
varies greatly in shape, being oval, nearly spherical, or cylindrical,
more or less swollen in the upper part, or constricted round the
middle, and either straight or curved. When the ovarium is short and
oval the interior structure does not differ from that of _C. maxima_
and _pepo_, but when it is elongated the carpels occupy only the
terminal and swollen portion. I may add that in one variety of the
cucumber (_Cucumis sativus_) the fruit regularly contains five carpels
instead of three.[754] I presume that it will not be disputed that we
here have instances of great variability in organs of the highest
physiological importance, and with most plants of the highest
classificatory importance.
Sageret[755] and Naudin found that the cucumber (_C. sativus_) could
not be crossed with any other species of the genus; therefore no doubt
it is specifically distinct from the melon. This will appear to most
persons a superfluous statement; yet we hear from Naudin[756] that
there is a race {360} of melons, in which the fruit is so like that of
the cucumber, "both externally and internally, that it is hardly
possible to distinguish the one from the other except by the leaves."
The varieties of the melon seem to be endless, for Naudin after six
years' study has not come to the end of them: he divides them into ten
sections, including numerous sub-varieties which all intercross with
perfect ease.[757] Of the forms considered by Naudin to be varieties,
botanists have made thirty distinct species! "and they had not the
slightest acquaintance with the multitude of new forms which have
appeared since their time." Nor is the creation of so many species at
all surprising when we consider how strictly their characters are
transmitted by seed, and how wonderfully they differ in appearance:
"Mira est quidem foliorum et habitus diversitas, sed multo magis
fructuum," says Naudin. The fruit is the valuable part, and this, in
accordance with the common rule, is the most modified part. Some melons
are only as large as small plums, others weigh as much as sixty-six
pounds. One variety has a scarlet fruit! Another is not more than an
inch in diameter, but sometimes more than a yard in length, "twisting
about in all directions like a serpent." It is a singular fact that in
this latter variety many parts of the plant, namely, the stems, the
footstalks of the female flowers, the middle lobe of the leaves, and
especially the ovarium, as well as the mature fruit, all show a strong
tendency to become elongated. Several varieties of the melon are
interesting from assuming the characteristic features of distinct
species and even of distinct though allied genera: thus the
serpent-melon has some resemblance to the fruit of _Trichosanthes
anguina_; we have seen that other varieties closely resemble cucumbers;
some Egyptian varieties have their seeds attached to a portion of the
pulp, and this is characteristic of certain wild forms. Lastly, a
variety of melon from Algiers is remarkable from announcing its
maturity by "a spontaneous and almost sudden dislocation," when deep
cracks suddenly appear, and the fruit falls to pieces; and this occurs
with the wild _C. momordica_. Finally, M. Naudin well remarks that this
"extraordinary production of races and varieties by a single species,
and their permanence when not interfered with by crossing, are
phenomena well calculated to cause reflection."
USEFUL AND ORNAMENTAL TREES.
Trees deserve a passing notice on account of the numerous varieties
which they present, differing in their precocity, in their manner of
growth, foliage, and bark. Thus of the common ash (_Fraxinus
excelsior_) the catalogue of Messrs. Lawson of Edinburgh includes
twenty-one varieties, some of which differ much in their bark; there is
a yellow, a streaked reddish-white, a purple, a wart-barked and a
fungous-barked variety.[758] Of hollies no less than eighty-four
varieties are grown alongside each other in Mr. {361} Paul's
nursery.[759] In the case of trees, all the recorded varieties, as far
as I can find out, have been suddenly produced by one single act of
variation. The length of time required to raise many generations, and
the little value set on the fanciful varieties, explains how it is that
successive modifications have not been accumulated by selection; hence,
also it follows that we do not here meet with sub-varieties subordinate
to varieties, and these again subordinate to higher groups. On the
Continent, however, where the forests are more carefully attended to
than in England, Alph. De Candolle[760] says that there is not a
forester who does not search for seeds from that variety which he
esteems the most valuable.
Our useful trees have seldom been exposed to any great change of
conditions; they have not been richly manured, and the English kinds
grow under their proper climate. Yet in examining extensive beds of
seedlings in nursery-gardens considerable differences may be generally
observed in them; and whilst touring in England I have been surprised
at the amount of difference in the appearance of the same species in
our hedgerows and woods. But as plants vary so much in a truly wild
state, it would be difficult for even a skilful botanist to pronounce
whether, as I believe to be the case, hedgerow trees vary more than
those growing in a primeval forest. Trees when planted by man in woods
or hedges do not grow where they would naturally be able to hold their
place against a host of competitors, and are therefore exposed to
conditions not strictly natural: even this slight change would probably
suffice to cause seedlings raised from such trees to be variable.
Whether or not our half-wild English trees, as a general rule, are more
variable than trees growing in their native forests, there can hardly
be a doubt that they have yielded a greater number of strongly-marked
and singular variations of structure.
In manner of growth, we have weeping or pendulous varieties of the
willow, ash, elm, oak, and yew, and other trees; and this weeping habit
is sometimes inherited, though in a singularly capricious manner. In
the Lombardy poplar, and in certain fastigate or pyramidal varieties of
thorns, junipers, oaks, &c., we have an opposite kind of growth. The
Hessian oak,[761] which is famous from its fastigate habit and size,
bears hardly any resemblance in general appearance to a common oak;
"its acorns are not sure to produce plants of the same habit; some,
however, turn out the same as the parent-tree." Another fastigate oak
is said to have been found wild in the Pyrenees, and this is a
surprising circumstance; it generally comes so true by seed, that De
Candolle considered it as specifically distinct.[762] The fastigate
Juniper (_J. suecica_) likewise transmits its character by seed.[763]
Dr. Falconer informs me that in the Botanic Gardens at Calcutta the
great heat causes apple-trees to become fastigate; and we {362} thus
see the same result following from the effects of climate and from an
innate spontaneous tendency.[764]
In foliage we have variegated leaves which are often inherited; dark
purple or red leaves, as in the hazel, barberry, and beech, the colour
in these two latter trees being sometimes strongly and sometimes weakly
inherited;[765] deeply-cut leaves; and leaves covered with prickles, as
in the variety of the holly well called _ferox_, which is said to
reproduce itself by seed.[766] In fact, nearly all the peculiar
varieties evince a tendency, more or less strongly marked, to reproduce
themselves by seed.[767] This is to a certain extent the case,
according to Bose,[768] with three varieties of the elm, namely, the
broad-leafed, lime-leafed, and twisted elm, in which latter the fibres
of the wood are twisted. Even with the heterophyllous hornbeam
(_Carpinus betulus_), which bears on each twig leaves of two shapes,
"several plants raised from seed all retained the same
peculiarity."[769] I will add only one other remarkable case of
variation in foliage, namely, the occurrence of two sub-varieties of
the ash with simple instead of pinnated leaves, and which generally
transmit their character by seed.[770] The occurrence, in trees
belonging to widely different orders, of weeping and fastigate
varieties, and of trees bearing deeply cut, variegated, and purple
leaves, shows that these deviations of structure must result from some
very general physiological laws.
Differences in general appearance and foliage, not more strongly marked
than those above indicated, have led good observers to rank as distinct
species certain forms which are now known to be mere varieties. Thus a
plane-tree long cultivated in England was considered by almost every
one as a North American species; but is now ascertained by old records,
as I am informed by Dr. Hooker, to be a variety. So again the _Thuja
pendula_ or _filiformis_ was ranked by such good observers as Lambert,
Wallich, and others as a true species; but it is now known that the
original plants, five in number, suddenly appeared in a bed of
seedlings, raised at Mr. Loddige's nursery, from _T. orientalis_; and
Dr. Hooker has adduced excellent evidence that at Turin seeds of _T.
pendula_ have reproduced the parent-form, _T. orientalis_.[771]
Every one must have noticed how certain individual trees regularly put
forth and shed their leaves earlier or later than others of the same
species. There is a famous horse-chesnut in the Tuileries which is
named from {363} leafing so much earlier than the others. There is also
an oak near Edinburgh which retains its leaves to a very late period.
These differences have been attributed by some authors to the nature of
the soil in which the trees grow; but Archbishop Whately grafted an
early thorn on a late one, and _vice versa_, and both grafts kept to
their proper periods, which differed by about a fortnight, as if they
still grew on their own stocks.[772] There is a Cornish variety of the
elm which is almost an evergreen, and is so tender that the shoots are
often killed by the frost; and the varieties of the Turkish oak (_Q.
cerris_) may be arranged as deciduous, sub-evergreen, and
evergreen.[773]
_Scotch Fir_ (_Pinus sylvestris_).--I allude to this tree as it bears
on the question of the greater variability of our hedgerow trees
compared with those under strictly natural conditions. A well-informed
writer[774] states that the Scotch fir presents few varieties in its
native Scotch forests; but that it "varies much in figure and foliage,
and in the size, shape, and colour of its cones, when several
generations have been produced away from its native locality." There is
little doubt that the highland and lowland varieties differ in the
value of their timber, and that they can be propagated truly by seed;
thus justifying Loudon's remark, that "a variety is often of as much
importance as a species, and sometimes far more so."[775] I may mention
one rather important point in which this tree occasionally varies; in
the classification of the Coniferae, sections are founded on whether
two, three, or five leaves are included in the same sheath; the Scotch
fir has properly only two leaves thus enclosed, but specimens have been
observed with groups of three leaves in a sheath.[776] Besides these
differences in the semi-cultivated Scotch fir, there are in several
parts of Europe natural or geographical races, which have been ranked
by some authors as distinct species.[777] Loudon[778] considers _P.
pumilio_, with its several sub-varieties, as _Mughus_, _nana_, &c.,
which differ much when planted in different soils and only come
"tolerably true from seed," as alpine varieties of the Scotch fir; if
this were proved to be the case, it would be an interesting fact as
showing that dwarfing from long exposure to a severe climate is to a
certain extent inherited.
The _Hawthorn_ (_Crataegus oxycantha_) has varied much. Besides endless
slighter variations in the form of the leaves, and in the size,
hardness, fleshiness, and shape of the berries, Loudon[779] enumerates
twenty-nine well-marked varieties. Besides those cultivated for their
pretty flowers, there are others with golden-yellow, black, and whitish
berries; others {364} with woolly berries, and others with recurved
thorns. Loudon truly remarks that the chief reason why the hawthorn has
yielded more varieties than most other trees, is that curious
nurserymen select any remarkable variety out of the immense beds of
seedlings which are annually raised for making hedges. The flowers of
the hawthorn usually include from one to three pistils; but in two
varieties, named _Monogyna_ and _Sibirica_, there is only a single
pistil; and d'Asso states that the common thorn in Spain is constantly
in this state.[780] There is also a variety which is apetalous, or has
its petals reduced to mere rudiments. The famous Glastonbury thorn
flowers and leafs towards the end of December, at which time it bears
berries produced from an earlier crop of flowers.[781] It is worth
notice that several varieties of the hawthorn, as well as of the lime
and juniper, are very distinct in their foliage and habit whilst young,
but in the course of thirty or forty years become extremely like each
other;[782] thus reminding us of the well-known fact that the deodar,
the cedar of Lebanon, and that of the Atlas, are distinguished with the
greatest ease whilst young, but with difficulty when old.
FLOWERS.
I shall not for several reasons treat the variability of plants which
are cultivated for their flowers alone at any great length. Many of our
favourite kinds in their present state are the descendants of two or
more species crossed and commingled together, and this circumstance
alone would render it difficult to detect the differences due to
variation. For instance, our Roses, Petunias, Calceolarias, Fuchsias,
Verbenas, Gladioli, Pelargoniums, &c., certainly have had a multiple
origin. A botanist well acquainted with the parent-forms would probably
detect some curious structural differences in their crossed and
cultivated descendant; and he would certainly observe many new and
remarkable constitutional peculiarities. I will give a few instances,
all relating to the Pelargonium, and taken chiefly from Mr. Beck,[783]
a famous cultivator of this plant: some varieties require more water
than others; some are "very impatient of the knife if too greedily used
in making cuttings;" some, when potted, scarcely "show a root at the
outside of the ball of the earth;" one variety requires a certain
amount of confinement in the pot to make it throw up a flower-stem;
some varieties bloom well at the commencement of the season, others at
the close; one variety is known,[784] which will stand "even pine-apple
top and bottom heat, without looking any more drawn than if it had
stood in a common greenhouse; and Blanche Fleur seems as if made on
purpose for growing in winter, like many bulbs, and to rest all
summer." These odd constitutional peculiarities would fit a plant when
growing in a state of nature for widely different circumstances and
climates.
{365}
Flowers possess little interest under our present point of view,
because they have been almost exclusively attended to and selected for
their beautiful colours, size, perfect outline, and manner of growth.
In these particulars hardly one long-cultivated flower can be named
which has not varied greatly. What does a florist care for the shape
and structure of the organs of fructification, unless, indeed, they add
to the beauty of the flower? When this is the case, flowers become
modified in important points; stamens and pistils may be converted into
petals, and additional petals may be developed, as in all double
flowers. The process of gradual selection by which flowers have been
rendered more and more double, each step in the process of conversion
being inherited, has been recorded in several instances. In the
so-called double flowers of the Compositae, the corollas of the central
florets are greatly modified, and the modifications are likewise
inherited. In the columbine _(Aquilegia vulgaris)_ some of the stamens
are converted into petals having the shape of nectaries, one neatly
fitting into the other; but in one variety they are converted into
simple petals.[785] In the hose and hose primulae, the calyx becomes
brightly coloured and enlarged so as to resemble a corolla; and Mr. W.
Wooler informs me that this peculiarity is transmitted; for he crossed
a common polyanthus with one having a coloured calyx,[786] and some of
the seedlings inherited the coloured calyx during at least six
generations. In the "hen-and-chicken" daisy the main flower is
surrounded by a brood of small flowers developed from buds in the axils
of the scales of the involucre. A wonderful poppy has been described,
in which the stamens are converted into pistils; and so strictly was
this peculiarity inherited that, out of 154 seedlings, one alone
reverted to the ordinary and common type.[787] Of the cock's-comb
(_Celosia cristata_), which is an annual, there are several races in
which the flower-stem is wonderfully "fasciated" or compressed; and one
has been exhibited[788] actually eighteen inches in breadth. Peloric
races of _Gloxinia speciosa_ and _Antirrhinum majus_ can be propagated
by seed, and they differ in a wonderful manner from the typical form
both in structure and appearance.
A much more remarkable modification has been recorded by Sir William
and Dr. Hooker[789] in _Begonia frigida_. This plant properly produces
male and female flowers on the same fascicles; and in the female
flowers the perianth is superior; but a plant at Kew produced, besides
the ordinary flowers, others which graduated towards a perfect
hermaphrodite structure; and in these flowers the perianth was
inferior. To show the importance of this modification under a
classificatory point of view, I may quote what Prof. Harvey says,
namely, that had it "occurred in a state of nature, and had a botanist
collected a plant with such flowers, he would not only have {366}
placed it in a distinct genus from Begonia, but would probably have
considered it as the type of a new natural order." This modification
cannot in one sense be considered as a monstrosity, for analogous
structures naturally occur in other orders, as with Saxifragas and
Aristolochiaceae. The interest of the case is largely added to by Mr. C.
W. Crocker's observation that seedlings from the _normal_ flowers
produced plants which bore, in about the same proportion as the
parent-plant, hermaphrodite flowers having inferior perianths. The
hermaphrodite flowers fertilised with their own pollen were sterile.
If florists had attended to, selected, and propagated by seed other
modifications of structure besides those which are beautiful, a host of
curious varieties would certainly have been raised; and they would
probably have transmitted their characters so truly that the cultivator
would have felt aggrieved, as in the case of culinary vegetables, if
his whole bed had not presented a uniform appearance. Florists have
attended in some instances to the leaves of their plant, and have thus
produced the most elegant and symmetrical patterns of white, red, and
green, which, as in the case of the pelargonium, are sometimes strictly
inherited.[790] Any one who will habitually examine highly-cultivated
flowers in gardens and greenhouses will observe numerous deviations in
structure; but most of these must be ranked as mere monstrosities, and
are only so far interesting as showing how plastic the organisation
becomes under high cultivation. From this point of view such works as
Professor Moquin-Tandon's 'Teratologie' are highly instructive.
_Roses._--These flowers offer an instance of a number of forms
generally ranked as species, namely, _R. centifolia_, _gallica_,
_alba_, _damascena_, _spinosissima_, _bracteata_, _Indica_,
_semperflorens_, _moschata_, &c., which have largely varied and been
intercrossed. The genus Rosa is a notoriously difficult one, and,
though some of the above forms are admitted by all botanists to be
distinct species, others are doubtful; thus, with respect to the
British forms, Babington makes seventeen, and Bentham only five
species. The hybrids from some of the most distinct forms--for
instance, from _R. Indica_, fertilised by the pollen of _R.
centifolia_--produce an abundance of seed; I state this on the
authority of Mr. Rivers,[791] from whose work I have drawn most of the
following statements. As almost all the aboriginal forms brought from
different countries have been crossed and recrossed, it is no wonder
that Targioni-Tozzetti, in speaking of the common roses of the Italian
gardens, remarks that "the native country and precise form of the wild
type of most of them are involved in much uncertainty."[792]
Nevertheless Mr. Rivers in referring to _R. Indica_ (p. 68) says that
the descendants of each group may generally be recognised by a close
observer. The same author often speaks of roses as having been a little
hybridised; but {367} it is evident that in very many cases the
differences due to variation and to hybridisation can now only be
conjecturally distinguished.
The species have varied both by seed and by buds; such modified buds
being often called by gardeners sports. In the following chapter I
shall fully discuss this latter subject, and shall show that
bud-variations can be propagated not only by grafting and budding, but
often even by seed. Whenever a new rose appears with any peculiar
character, however produced, if it yields seed, Mr. Rivers (p. 4) fully
expects it to become the parent-type of a new family. The tendency to
vary is so strong in some kinds, as in the Village Maid (Rivers, p.
16), that when grown in different soils it varies so much in colour
that it has been thought to form several distinct kinds. Altogether the
number of kinds is very great: thus M. Desportes, in his Catalogue for
1829, enumerates 2562 as cultivated in France; but no doubt a large
proportion of these are merely nominal.
It would be useless to specify the many points of difference between
the various kinds, but some constitutional peculiarities may be
mentioned. Several French roses (Rivers, p. 12) will not succeed in
England; and an excellent horticulturist[793] remarks, that "Even in
the same garden you will find that a rose that will do nothing under a
south wall will do well under a north one. That is the case with Paul
Joseph here. It grows strongly and blooms beautifully close to a north
wall. For three years seven plants have done nothing under a south
wall." Many roses can be forced, "many are totally unfit for forcing,
among which is General Jacqueminot."[794] From the effects of crossing
and variation Mr. Rivers enthusiastically anticipates (p. 87) that the
day will come when all our roses, even moss-roses, will have evergreen
foliage, brilliant and fragrant flowers, and the habit of blooming from
June till November. "A distant view this seems, but perseverance in
gardening will yet achieve wonders," as assuredly it has already
achieved wonders.
It may be worth while briefly to give the well-known history of one
class of roses. In 1793 some wild Scotch roses (_R. spinosissima_) were
transplanted into a garden;[795] and one of these bore flowers slightly
tinged with red, from which a plant was raised with semi-monstrous
flowers, also tinged with red; seedlings from this flower were
semi-double, and by continued selection, in about nine or ten years,
eight sub-varieties were raised. In the course of less than twenty
years these double Scotch roses had so much increased in number and
kind, that twenty-six well-marked varieties, classed in eight sections,
were described by Mr. Sabine. In 1841[796] it is said that three
hundred varieties could be procured in the nursery-gardens near
Glasgow; and these are described as blush, crimson, purple, red,
marbled, two-coloured, white, and yellow, and as differing much in the
size and shape of the flower.
{368}
_Pansy or Heartsease_ (_Viola tricolor_, &c.).--The history of this
flower seems to be pretty well known; it was grown in Evelyn's garden
in 1687; but the varieties were not attended to till 1810-1812, when
Lady Monke, together with Mr. Lee the well-known nurseryman,
energetically commenced their culture; and in the course of a few years
twenty varieties could be purchased.[797] At about the same period,
namely in 1813 or 1814, Lord Gambier collected some wild plants, and
his gardener, Mr. Thomson, cultivated them together with some common
garden varieties, and soon effected a great improvement. The first
great change was the conversion of the dark lines in the centre of the
flower into a dark eye or centre, which at that period had never been
seen, but is now considered one of the chief requisites of a first-rate
flower. In 1835 a book entirely devoted to this flower was published,
and four hundred named varieties were on sale. From these circumstances
this plant seemed to me worth studying, more especially from the great
contrast between the small, dull, elongated, irregular flowers of the
wild pansy, and the beautiful, flat, symmetrical, circular, velvet-like
flowers, more than two inches in diameter, magnificently and variously
coloured, which are exhibited at our shows. But when I came to inquire
more closely, I found that, though the varieties were so modern, yet
that much confusion and doubt prevailed about their parentage. Florists
believe that the varieties[798] are descended from several wild stocks,
namely, _V. tricolor_, _lutea_, _grandiflora_, _amoena_, and _Altaica_,
more or less intercrossed. And when I looked to botanical works to
ascertain whether these forms ought to be ranked as species, I found
equal doubt and confusion. _Viola Altaica_ seems to be a distinct form,
but what part it has played in the origin of our varieties I know not;
it is said to have been crossed with _V. lutea_. _Viola amoena_[799] is
now looked at by all botanists as a natural variety of _V.
grandiflora_; and this and _V. sudetica_ have been proved to be
identical with _V. lutea_. The latter and _V. tricolor_ (including its
admitted variety _V. arvensis_) are ranked as distinct species by
Babington; and likewise by M. Gay,[800] who has paid particular
attention to the genus; but the specific distinction between _V. lutea_
and _tricolor_ is chiefly grounded on the one being strictly and the
other not strictly perennial, as well as on some other slight and
unimportant differences in the form of the stem and stipules. Bentham
unites these two forms; and a high authority on such matters, Mr. H. C.
Watson,[801] says that, "while _V. tricolor_ passes into _V. arvensis_
on the one side, it approximates so much towards _V. lutea_ and _V.
Curtisii_ on the other side, that a distinction becomes scarcely more
easy between them."
{369}
Hence, after having carefully compared numerous varieties, I gave up
the attempt as too difficult for any one except a professed botanist.
Most of the varieties present such inconstant characters, that when
grown in poor soil, or when flowering out of their proper season, they
produce differently coloured and much smaller flowers. Cultivators
speak of this or that kind as being remarkably constant or true; but by
this they do not mean, as in other cases, that the kind transmits its
character by seed, but that the individual plant does not change much
under culture. The principle of inheritance, however, does hold good to
a certain extent even with the fleeting varieties of the Heartease, for
to gain good sorts it is indispensable to sow the seed of good sorts.
Nevertheless in every large seed-bed a few almost wild seedlings often
reappear through reversion. On comparing the choicest varieties with
the nearest allied wild forms, besides the difference in the size,
outline, and colour of the flowers, the leaves are seen sometimes to
differ in shape, as does the calyx occasionally in the length and
breadth of the sepals. The differences in the form of the nectary more
especially deserve notice; because characters derived from this organ
have been much used in the discrimination of most of the species of
Viola. In a large number of flowers compared in 1842 I found that in
the greater number the nectary was straight; in others the extremity
was a little turned upwards, or downwards, or inwards, so as to be
completely hooked; in others, instead of being hooked, it was first
turned rectangularly downwards, and then backwards and upwards; in
others the extremity was considerably enlarged; and lastly, in some the
basal part was depressed, becoming, as usual, laterally compressed
towards the extremity. In a large number of flowers, on the other hand,
examined by me in 1856 from a nursery-garden in a different part of
England, the nectary hardly varied at all. Now M. Gay says that in
certain districts, especially in Auvergne, the nectary of the wild _V.
grandiflora_ varies in the manner just described. Must we conclude from
this that the cultivated varieties first mentioned were all descended
from _V. grandiflora_, and that the second lot, though having the same
general appearance, were descended from _V. tricolor_, of which the
nectary, according to M. Gay, is subject to little variation? Or is it
not more probable that both these wild forms would be found under other
conditions to vary in the same manner and degree, thus showing that
they ought not to be ranked as specifically distinct?
The _Dahlia_ has been referred to by almost every author who has
written on the variation of plants, because it is believed that all the
varieties are descended from a single species, and because all have
arisen since 1802 in France, and since 1804 in England.[802] Mr. Sabine
remarks that "it seems as if some period of cultivation had been
required before the fixed qualities of the native plant gave way and
began to sport into those changes which now so delight us."[803] The
flowers have been greatly modified in shape from a flat to a globular
form. Anemone and {370} ranunculus-like races,[804] which differ in the
form and arrangement of the florets, have arisen; also dwarfed races,
one of which is only eighteen inches in height. The seeds vary much in
size. The petals are uniformly coloured or tipped or striped, and
present an almost infinite diversity of tints. Seedlings of fourteen
different colours[805] have been raised from the same plant; yet, as
Mr. Sabine has remarked, "many of the seedlings follow their parents in
colour." The period of flowering has been considerably hastened, and
this has probably been effected by continued selection. Salisbury,
writing 1808, says that they then flowered from September to November;
in 1828 some new dwarf varieties began flowering in June;[806] and Mr.
Grieve informs me that the dwarf purple Zelinda in his garden is in
full bloom by the middle of June and sometimes even earlier. Slight
constitutional differences have been observed between certain
varieties: thus, some kinds succeed much better in one part of England
than in another;[807] and it has been noticed that some varieties
require much more moisture than others.[808]
Such flowers as the carnation, common tulip, and hyacinth, which are
believed to be descended, each from a single wild form, present
innumerable varieties, differing almost exclusively in the size, form,
and colour of the flowers. These and some other anciently cultivated
plants which have been long propagated by offsets, pipings, bulbs, &c.,
become so excessively variable, that almost each new plant raised from
seed forms a new variety, "all of which to describe particularly," as
old Gerarde wrote in 1597, "were to roll Sisyphus's stone, or to number
the sands."
_Hyacinth_ (_Hyacinthus orientalis_).--It may, however, be worth while
to give a short account of this plant, which was introduced into
England in 1596 from the Levant.[809] The petals of the original
flower, says Mr. Paul, were narrow, wrinkled, pointed, and of a flimsy
texture; now they are broad, smooth, solid, and rounded. The erectness,
breadth, and length of the whole spike, and the size of the flowers,
have all increased. The colours have been intensified and diversified.
Gerarde, in 1597, enumerates four, and Parkinson, in 1629, eight
varieties. Now the varieties are very numerous, and they were still
more numerous a century ago. Mr. Paul remarks that "it is interesting
to compare the Hyacinths of 1629 with those of 1864, and to mark the
improvement. Two hundred and thirty-five years have elapsed since then,
and this simple flower serves well to illustrate the great fact that
the original forms of nature do not remain fixed and stationary, at
least when brought under cultivation. While looking at the extremes, we
must not however forget that there are intermediate stages which are
for the most part lost to us. Nature will {371} sometimes indulge
herself with a leap, but as a rule her march is slow and gradual." He
adds that the cultivator should have "in his mind an ideal of beauty,
for the realisation of which he works with head and hand." We thus see
how clearly Mr. Paul, an eminently successful cultivator of this
flower, appreciates the action of methodical selection.
In a curious and apparently trustworthy treatise, published at
Amsterdam[810] in 1768, it is stated that nearly 2000 sorts were then
known; but in 1864 Mr. Paul found only 700 in the largest garden at
Haarlem. In this treatise it is said that not an instance is known of
any one variety reproducing itself truly by seed: the white kinds,
however, now[811] almost always yield white hyacinths, and the yellow
kinds come nearly true. The hyacinth is remarkable from having given
rise to varieties with bright blue, pink, and distinctly yellow
flowers. These three primary colours do not occur in the varieties of
any other species; nor do they often all occur even in the distinct
species of the same genus. Although the several kinds of hyacinths
differ but slightly from each other except in colour, yet each kind has
its own individual character, which can be recognised by a highly
educated eye; thus the writer of the Amsterdam treatise asserts (p. 43)
that some experienced florists, such as the famous G. Voorholm, seldom
failed in a collection of above twelve hundred sorts to recognise each
variety by the bulb alone! This same writer mentions some few singular
variations: for instance, the hyacinth commonly produces six leaves,
but there is one kind (p. 35) which scarcely ever has more than three
leaves; another never more than five; whilst others regularly produce
either seven or eight leaves. A variety, called la Coriphee, invariably
produces (p. 116) two flower-stems, united together and covered by one
skin. The flower-stem in another kind (p. 128) comes out of the ground
in a coloured sheath, before the appearance of the leaves, and is
consequently liable to suffer from frost. Another variety always pushes
a second flower-stem after the first has begun to develop itself.
Lastly, white hyacinths with red, purple, or violet centres (p. 129)
are the most liable to rot. Thus, the hyacinth, like so many previous
plants, when long cultivated and closely watched, is found to offer
many singular variations.
In the two last chapters I have given in some detail the range of
variation, and the history, as far as known, of a considerable number of
plants, which have been cultivated for various purposes. But some of the
most variable plants, such as Kidney-beans, Capsicum, Millets, Sorghum,
&c., have been passed over; for botanists are not agreed which kinds ought
to rank as species and which as varieties; and the wild parent-species are
unknown.[812] Many plants long cultivated in tropical {372} countries, such
as the Banana, have produced numerous varieties; but as these have never
been described with even moderate care, they also are here passed over.
Nevertheless a sufficient, and perhaps more than sufficient, number of
cases have been given, so that the reader may be enabled to judge for
himself on the nature and extent of the variation which cultivated plants
have undergone.
* * * * *
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