flower-stalk, it is true, is of rapid growth, its whole stature having
been attained within three or four weeks. But those massive leaves! Each
of these lasts many years, and their development is as slow as that of
the flower-stalk is rapid. Certainly we cannot assign to this
individual, in the very vigour of its inflorescence, an antiquity less
than half a century, and perhaps it may be considerably more.
You are altogether wrong; for it is but just called into existence.
[Illustration: TRAVELLER'S TREE.]
We pass on, and pause before a noble example of one of the stateliest of
plants,--the Traveller's Tree (_Urania speciosa_). It is a great
Musaceous plant, resembling one of those fans which in the Southern
States of America are made by ladies out of the broad tail-feathers of a
turkey. Its leaves, of vast size, consist of a broad oblong lamina of
the most brilliant green hue, divided equally by a midrib which descends
in a smooth cylindrical petiole, much longer than the lamina (which is
itself eight feet or more in length). Each leaf-stalk terminates below
in a great demi-sheath, out of which springs another, in a zigzag or
distichous fashion, the whole diverging, as they rise, in the same
plane.
Below the alternately-sheathing leaves, of which there are but eight at
present existing, there are the bases of others, now dead, which, when
alive, evidently followed the same arrangement; and these give place yet
lower to rings, each partly surrounding a massive conical stem.
I fear we have no criterion for determining the exact age of such a
plant as this from actual observations on its rate of growth. From the
fewness of its existing leaves they probably endure a considerable time;
but at all events here are indubitable evidences of successive
generations of leaves which are now past and gone; some of which are
represented by withered rib-bases, while older ones have left but the
scars which indicate the positions on the trunk where once they stood.
Here are distinct testimonies to the lapse of a considerable period of
time since the magnificent _Urania_, began its existence. Yet we should
err egregiously by giving credence to them, since these developments are
all _prochronic_.
"What a lovely butterfly!" Nay, it is a flower: though it dances in the
air with an insect's fluttering flight, and seems to present in its
broad wings of yellow and orange, and in its long and slender members,
an insect's form and hues, it is but a flower fixed at the end of a
lengthened stalk, which hangs from, a mass of leaves and bulbs, seated
in the fork of this huge mahogany-tree.
We will neglect the flower, curious and beautiful as it is, and examine
this crowded mass of roots and fleshy leaves and oval bulbs.
Tracing the slender lengthened footstalk to its origin, we see that it
springs from the lower part of a flat, ovate, or nearly round, ridged,
pseudo-bulb, of a purplish-green hue, of which there are many, much
crowded together. The point of issue of the flower-stalk is concealed by
an enveloping husky scale, which is the withered condition of a former
leaf. From the base of another bulb a thick obtuse cone is pushing
forth, which is the commencement of a new leaf-shoot; and here is one
considerably advanced. In this latter there is nothing very remarkable;
it is a thick, growing shoot, formed by fleshy leaves nearly doubled
together, each sheathed by its predecessor. But soon this will cease to
grow, and the point will dilate into an oval bulb, which will be a
reservoir of nutriment for the future flower. In fact it will add
another to the matted mass of bulbs which are already accumulated,
crowned with two great thick, leathery, ovate, brown-spotted leaves, and
marked with the scars of the leaves which are now growing, but which
will then have sloughed away.
In this _Oncidium_, then, we have evidently a record of many bygone
processes. Before the flower could open, the flower-stalk must have been
developed; before this, the pseudo-bulb must have been formed; before
this, there must have been a well-formed leaf-shoot, which must have
been first a conical bud pushing forth from some anterior bulb;--or, if
that shoot had been the first of the mass, then it must have looked back
to a seed, which of course looked back to the capsule of a pre-existent
flower, and so on.
Yet this is all fallacious; for the Butterfly-flower is but just
created.
As beautiful, if less curious, is the crowded spike of purple blossom
that adorns the tall stalk of this terrestrial Orchis. The flower-stalk
springs from the midst of a few large spotted leaves, which terminate
below in an irregular fleshy tuber of glutinous consistence. This tuber
is shrivelled, and is in process of exhaustion and decay; but a
horizontal stem has pushed out underground, which has at its extremity a
second tuber, as yet immature, but plump and swelling. This growing
tuber contains the elements of the leaves and flower-spike of next
season: the shrivelling one was, last year at this period, in exactly
the same condition as the swelling one is now; it too was pushed out
horizontally from a preceding one which was then shrivelling, and so
backward. These pre-existing stages can with certainty be announced by
the vegetable physiologist; who yet would be deceived in this instance,
because the plant has been but just created.
This elegant _Gladiolus_ that displays its tall spike of crimson
blossoms from the midst of its flattened folded leaves, affords us a
similar example of retrospective energy. If I dig away the light soil
from around its base, I discover two globose corms, fleshy swellings of
the stem, accumulations of nutriment obtained during the vegetative
activity of the plant, and destined to support it during the season of
inaction, and therefore stored up for that purpose.
[Illustration: CORM OF GLADIOLUS IN JUNE.]
The uppermost of these globose corms is that of the present season; it
is as yet small and immature, being in process of formation by the
assimilation, consolidation, and deposition of new matter by the action
of the leaves. This is sheathed in the tubular bases of the leaves,
which expand above; and it is seated on a larger, riper, and more
spherical corm, which is wrapped in a brown fibrous skin. This is the
matter which was deposited in the course of last spring and summer, and
the brown skin is the remains of the leaves of last year. This corm has
remained inactive, since the decay of last year's leaves, until this
winter, when the root fibres, which we see descending from the lower
surface, began to form, and an upward prolongation of the stem followed,
which, as it grew, swelled into the upper corm.
In the centre of the under surface of the corm of last season, in a
depression surrounded by the white root-fibres, there are some almost
decayed remains of a deep brown hue. These are the last vestiges of the
preceding year's corm, and they exhibit the condition in which the large
corm will be next spring, when the small half-formed one will be in the
state and position of this larger one, and will in like manner be
surmounted by its rising successor.
Thus there are in this plant ocular proofs of two years' history before
the present; yet these proofs are invalidated by the fact of its
creation this day.
Behold now that singular plant, the Grass-tree (_Kingia australis_),
displaying what seems an immense tuft of wiry grass elevated on the
summit of a trunk which is formed of the united bases of myriads of
decayed leaves, the representatives of many generations of these
organs. The silvery leaves which constitute the existing crown, and the
numerous spikes of blossom which stand up in a circle diverging from the
midst of them, give to this plant a most striking effect. That, however,
is not our present concern, but the evidences which we may be able to
gather from it of a previous history. For some distance below the living
leaves, the trunk is connected by the withered, hanging, but still
persistent leaves of several successive developments, a ragged drapery,
of which we might certainly say--
"----when unadorn'd, adorn'd the most."
The lower portion of the stem is, however, destitute of the decayed
leaves themselves, the lozenge-formed bases of them alone remaining,
still separable, indeed, but sufficiently compact to make in the
aggregate a sub-cylindrical column of loose texture, which may in
familiar parlance be termed a _trunk_. This portion is marked by
alternate enlargements and constrictions of the outline, which appear to
indicate seasonal growths.
The specimen before us is about twenty feet in height, exclusive of the
crown; supposing these swellings to mark a year's growth, and to be
continued in the same proportion on that part of the trunk which is
masked by the decayed leaves as on the exposed part, we should conclude
this tree to be about thirty-five years old; for there are about
thirty-four such swellings, each of which contains about four hundred of
the lozenge-shaped bases of the fallen leaves.[56]
Remember, however, that we are looking at the Grass-tree, not as it now
appears on the sandy plains of Western Australia, in the nineteenth
century, but as it came out of the hands of its Almighty Creator at some
precise but unknown period of past time.
This White Lily, crowned with its cluster of nodding flowers,
magnificently beautiful, each a fair emblem of the spotless purity of a
noble virgin--if we remove the soil from its base, we shall find that
the stem springs out of a fleshy bulb. This is covered with thick yellow
scales, by taking away each of which in turn, we see that the bulb is
made up of such, surrounding the central mass which has pushed upward,
in the form of the stalk, with its leaves and flowers.
[Illustration: SECTION OF LILY-BULB IN JULY.]
Now the whole of this beautiful array which we see was formed last
summer, when, if we had divided the bulb longitudinally, we should have
seen every leaf, every tiny blossom, folded together, and most snugly
packed within the encircling scales, which are, indeed, undeveloped
leaves; while from the base of the bulb so formed we should have seen
pushed up on the outside of it, but yet within the common envelope of
the exterior scales, the flower-stem of last season. There could not
possibly have been this raceme of virgin blossom, if it had not been
formed during the preceding season within the bulb; so that its
existence is a record of a year's growth at least.
Yet this is the first hour of the lovely Lily's life; an hour ago it was
not.
The face of the rugged cliff that rises perpendicularly above us was, a
few moments ago, quite naked and bare, or diversified only by a few
stunted prickly shrubs that sprang from its crevices. Now, by the mighty
fiat of God, it is in an instant festooned from top to bottom with a
most graceful drapery of round pale-green leaves, and slender stems no
thicker than whipcord, and multitudes of spiral tendrils that climb, and
hook, and catch, and entwine among the thorny bushes, and around the
angles and prominences of the rock. We trace this curtain of verdure
downwards, and find that it resolves itself into some half a dozen of
wiry-stems, that issue from different points of the surface of what
seems a boulder of brown stone, or a block of rough-hewn timber, at the
foot of the cliff.
[Illustration: TESTUDINARIA.]
This angular block is, however, worthy of closer examination. It is of
no definite form, huge and uncouth, lying as if cast accidentally on the
ground. Its whole surface is divided into a multitude of polyhedral
pieces, that look as if they had been cut into these forms by human
art. Each division has a small angular face, and its sides display close
parallel lines, all following the directions and angles of the outer
face, but each line enclosing a slightly wider area than the one above
it. These woody plates closely resemble in their angular forms and their
concentric lines the plates of a Tortoise's shell, and hence our
botanical friend, to whom we will appeal for an opinion as to the age of
the block, will call the generic name _Testudinaria_.
"Well, I cannot give you any very precise judgment on the matter. The
block itself is the tuber of a sort of yam, which grows above ground
instead of below. It is a woody mass of great age. The angular plates
are the bark, and they are so divided in consequence of the gradual
growth of the tuber, tearing open its periphery to obtain more room. The
concentric lines on the edges of the plates will not give us any
adequate idea of the age of the mass, for though they indicate seasonal
growths, the earlier layers have been worn away in the lapse of ages,
and there are many layers of bark that have not yet been burst by the
expansive force of the growing wood. It is known that these blocks are
of very slow growth; in tropical regions they last, with scarcely
perceptible increase, from generation to generation. From such vague
data as we possess, I might loosely conjecture this tuber to be a
thousand years old."
We thank our scientific friend, and think it a very satisfactory report
on an organism, which we saw called into existence five minutes ago,
before our eyes.
Come away; for I wish you to look at this _Encephalalartos_. A horrid
plant it is, a sort of caricature of the elegant Palms, somewhat as if a
founder had essayed a cocoa-nut tree in cast iron. Out of the thick,
rough, stiff stem spring a dozen of arching fronds, beset with sharp,
sword-shaped leaflets, but having the rigidity of horn, of a greyish
hue, all harsh and repulsive to excess. In the midst of this rigid
coronal sits the fruit, like an immense pine-cone.
The swelling column that constitutes the stem is but a mass of pith,
surrounded by a thin case of wood, and enclosed by the remains of former
leaves. The whole surface is covered with the lozenge-shaped scars of
these, in vast number. Thousands of these there must be in this trunk of
eight feet high, and a foot thick. The leaves of the existing crown are
few and very durable, so that it would be no unreasonable conjecture to
suppose that this great Cycadaceous plant is seven or eight centuries
old.
[Illustration: ENCEPHALARTOS.]
Nay, for this also has been created even now!
What shall we say to _this_ singular phenomenon? Observe yonder gigantic
Fig (_Ficus Australis_) growing out of the face of that vast rocky
precipice. It is not so much to the massive grandeur of the trunk, nor
to the widespread head of dense foliage, that I call your attention, as
to the broad expanse of roots, from the thickness of your body to that
of your little finger, which have crossed and interlaced and separated
and re-united, in all imaginable ways, until the whole forms a great
flat network of wood, investing the surface of the rock, and following
all its projections and angles with singular faithfulness, for a space
of many square yards.
Would you not say, admitting that the Figs are rapid growers, that many
years must have elapsed since the minute seed was dropped in yonder
crevice, by some vagrant parrot that wiped his beak after breakfast on
the point of rock? Would you not say that many years must have passed
from the time when the tiny shoot peeped from the rocky chink, to the
present moment, when the leafy honours of the crown above and the woody
wall of the roots below combine to repay the protection which the plant
in infancy received from its stony foster mother?
Of course you would; and most truly too, did you not know that the
Fig-tree is now rejoicing in the first hour of its new-created being.
So with its noble congener here, the many-trunked Banyan (_Ficus
Indica_). Although not an old tree, its canopy of broad downy leaves is
already supported by so many secondary trunks, that it is not easy to
say which of the larger stems is the mother trunk, and which the hopeful
daughters. Every one of these stems, some just protruding from the
horizontal limbs, others hanging midway between the leafy roof and the
earth, some just inserting their slender spongy tips into the soil,
others thick and pillar-like--is an evidence of progressive development,
and therefore of lapsed time; only for the qualifying fact, that the
development in this case is _prochronic_.
Here is the great _Euphorbia grandidens_ of Africa. Its stout trunk is
marked with a number of holes, some four or five inches apart, arranged
in perpendicular rows. In some cases they are rather depressions or
pittings than holes, and look like what would result from borings made
with an auger in pitch in warm weather, the margins of which had nearly
closed, subsequently. What is the explanation of these marks? They are
all records of time. From each of these spots once grew one of those
angular prickly branches, that look like our commonest sorts of
_Cactus_, and which are now confined to the summit of the trunk,
arching out from it, somewhat like the branches of a candlestick.
It is the habit of this plant, when the stem has acquired a certain
thickness, that the branches should, after a time, decay and drop off at
the point of their union with the trunk, or rather a little below the
surface, so as to leave the shallow holes or pits which we see. After
their decadence, the growing bark gradually swells around the scars, and
has a tendency to obliterate them. This may account for the
non-appearance of them on the lower parts of the stem.
Here, then, are demonstrations of several successive stages of
development. First, the stem must have been in existence before any
lateral branches could have sprung from it. Secondly, the branch shot
out. Thirdly, it put forth its spines and leaves. Fourthly, it died and
sloughed away. Fifthly, the growing bark encroached on, and finally
obliterated the cicatrice.
In this individual, all these stages are illusory, or rather they are
prochronic.
See this noble Tulip-tree (_Liriodendron tulipiferum_), a giant of this
primeval forest; its towering trunk is crowned with a head of large
massy foliage, of a rich deep verdure, among which shine numbers of
great golden tulip-like blossoms, as fragrant as beautiful.
It is, however, the leaves that grow on the terminal twigs that I wish
you specially to notice. These, which, as you see, are large, and of a
remarkably elegant form, are fixed at the end of long petioles, which
are set alternately on the twig. Notice, now, the manner of their
development; the young unexpanded leaves grow within two large leaf-like
bracts, forming an oval sac, which, as the young leaf increases, swell,
and at length burst, and are left on each side of the base of the
leaf-stalk. There is a succession of these. On this growing twig, for
instance, I find three leaves already expanded (_a a a_ in the
accompanying figure), and as many pairs of these bracts (_b b b_) at
their bases; the twig is terminated by a pair (_c_) convex outwardly,
and whose edges are in contact with each other; if, now, I cut off one
of these (as represented at _d_), I expose the next leaf (_e_) folded
together, and bent downward, in its pretty manner of _vernation_; beside
it is another pair of bracts (_f_), whose edges are not only in contact,
but mutually adherent, and that with considerable force. On tearing
these apart, I discover another smaller leaf, and another smaller pair
of adhering bracts, which again contain a similar set, only yet more
minute, and so on in succession, till I can no longer trace them.
[Illustration: TWIG OF TULIP-TREE.]
Now it is manifest that the uppermost of the three leaves, together with
the developing terminal bud, was at one time enclosed in the pair of
bracts immediately below its base; that, before that, the middle leaf,
with all above it, was similarly incarcerated in its own proper tracts;
and, at a period anterior to that, the lowest leaf also. Each pair of
bracts is therefore a record of a past period; and together they testify
to a succession of past periods.
And yet their combined testimony is utterly worthless, because the noble
tree was created in its magnificence this very day.
The beautiful twiner (_Bignonia_), which has cast its ample festoons
over the topmost branches of yonder towering Mora-tree, almost
concealing the natural foliage with its own elegantly pinnate leaves,
and adorning it with its gorgeous trumpet-shaped flowers, is
distinguished by a curious property, indicative of the years that have
passed over it. In its adult maturity, as we now see it--the glory of
this tropical forest--we should find, if we cut across the main stem,
that its wood is divided into lobes arranged in a radiate or star-like
fashion, like the divisions seen on dividing an orange transversely; and
these lobes are thirty-two in number.
But this condition has not existed through the life of the plant. The
wood has always been lobed, but the number of the divisions has varied,
and that in geometrical ratio. Before the present stage, the constituent
lobes were sixteen, which became thirty-two by the subdivision of each.
In an earlier stage there were eight lobes, and, earlier still, four,
which was the commencing number; the duplication having proceeded in
each case by the fission of each of the existing lobes into two.[57]
Now though this phenomenon will afford us, on the data we at present
possess, no insight into the age of the plant, considered as an actual
chronological period, an examination of a transverse section would
always determine which stage is then present, and, by consequence, how
many previous stages have been passed through. And thus we obtain a
distinct clue to the former history of the organism, though we cannot
mark it off into months and years.
Yet the fact of creation stultifies all the conclusions that we might
form from such premises; since it does, _ipso facto_, contradict every
such thing as a previous history.
On this _Anona_ there is an intruder more strictly parasitical; it is a
_Loranthus_, with long, club-shaped, richly-coloured blossoms. The
branches of the supporting tree--a nurse who feeds her foster-child on
her own vital juices--are over-spread for a large space with the shoots;
which, springing each from its own disk, appear like so many distinct
individuals, but are really all parts of a single plant, springing from
a single seed. (For this curious fact we are indebted to the
observations of Mr. Griffith, who has investigated the singular history
of these parasites.)
The ripe seeds firmly adhere to the substance on which they are applied,
by means of their viscid envelope, which soon hardens into a transparent
glue. In the course of two or three days, the radicle curves towards its
support, and, as soon as it reaches it, becomes dilated and flattened.
An union is gradually formed between the woody system of the parasite
and that of the stock, after which the former lives exclusively on the
latter, the fibres of the sucker-like root of the parasite expanding on
the wood of the support in the form of a _pate d'oie_. Up to that time
the parasite had been nourished by its own albumen, which is now
exhausted. As soon as the young parasite has acquired the height of one
or two inches, when an additional supply of nourishment is required, a
lateral shoot is sent out, which is, especially towards the point, of a
green colour. This at one, or two, and subsequently at various points,
adheres to the support by means of sucker-like productions, which are
precisely similar in structure and mode of attachment to the original
seminal one. The fibres of the parasite never penetrate beyond their
original attachment; in the adult the sucker-bearing shoots frequently
run to a considerable distance, many plants being literally covered with
parasites, all of which have originated from one and the same seed.[58]
[Illustration: YOUNG PLANT OF LORANTHUS.]
In this case, again, how delusive would be any inference of actual
lapse of time deduced from the condition of a plant, which had been
created as an adult capable of reproducing its race!