as compared with the tender grace of one they called Lady-fern
(_Asplenium filix-fœmina_)--we have an advance in the intricacy of
frond-division. Our page is not sufficiently large to represent the
whole of the frond, but the portion we give shows that the pinnæ are
themselves again divided into _pinnules_. This fern grows to a great
size, its rootstock very thick and woody, its fronds erect and three
or four feet high. As a rule the rachis and its continuation below the
leafy portion (_stipes_) are shaggy with loose golden-brown scales.
The spore-capsules are in little round heaps in rows along the pinnæ,
and each heap is covered by a thin kidney-shaped involucre. Note in
the unrolling of a young frond how beautifully the whole is packed
up. The lateral divisions of the pinnæ are rolled each on itself,
then the pinnæ are rolled up from their tips toward the rachis, and
finally the whole frond is coiled up from the tip downwards. This is
the characteristic _vernation_ of ferns, and differs greatly from the
packing of undeveloped leaves in the leaf-buds of flowering-plants.
The genus _Nephrodium_ (named from _nephros_, the kidneys, in
allusion to the involucre) contains half-a-dozen other British
species, of which the most frequent is the Broad Buckler Fern (_N.
spinulosum_), with arching fronds, broad at the base, the stipes
sparingly clothed with dark-brown scales. Pinnules toothed, the
teeth ending in long soft points. Damp woods.
Mountain fern (_N. oreopteris_), with habit of Male fern, but
stiffer, and of a yellow-green hue. Spore-heaps near the margins of
the pinnæ. High hills and mountain pastures.
=Field Horsetail= (_Equisetum arvense_).
The Horsetails are a small group of flowerless plants, quite
distinct from the ferns, though there are certain points in which
some resemblance may be traced. We have eight British species out
of twenty-five that are known to inhabit the earth. The most widely
distributed of these is the Field Horsetail (_E. arvense_), which
farmers regard as a pest. In common with the whole tribe it has a
creeping underground rootstock, from which more or less erect jointed
stems arise. If we break off one of these joints at its natural
articulation we shall observe that the ends are solid, and that the
upper extremity is crowned by a sheath ending in long pointed teeth,
into which the lower end of the next joint fitted. This leaf-sheath,
as it is called, is composed of a number of aborted leaves--the only
vestiges of leaves the plant possesses. Just below the leaf-sheath a
whorl of jointed branches is given off, each constructed in a manner
similar to the upright stem. If now we cut our main joint across its
middle with a sharp knife we shall find that it is tubular, a central
cavity occupying about one-third of its diameter. Between this cavity
and the exterior wall is a series of small tubes, somewhat egg-shaped
in outline, the smaller end towards the central cavity; alternating
with these and nearer the centre are a number of smaller circular
tubes. This section should always be made when in doubt as to the
species, for the shape and arrangement of these cavities differs in
each, as do the external ridges. The accompanying cuts represent
half-sections through the stems of the principal British species.
In this species there are about a dozen blunt ridges on the stem,
extending right to the points of the leaf-sheath. The branches are
four-angled, solid, and jointed and sheathed like the main stem. The
cells of the cuticle secrete silica in such quantity that the whole of
the vegetable matter may be got rid of by maceration, yet the form of
the stem will remain in this transparent skeleton of silica. Certain
species are used for polishing metal, under the name of Dutch Rushes.
[Illustration: =Corn Horsetail.=
Equisetum arvense.
--EQUISETACEÆ.--]
[Illustration: A.--=Scarlet Cup-moss.=
Cladonia cornucopioides.
B.--=Wall-Lichen.=
Physcia parietina.
--LICHENES.--]
[Illustration: Half-Sections through Horsetail Stems.
1. Equisetum maximum.
2. ” pratense.
3. ” arvense.
4. ” sylvaticum.
5. ” limosum.
6. ” palustre.
7. ” hyemale.]
So far we have been describing what is known as the barren
stem, because it ends in several unbranched joints, without any
fructification. Before these barren stems appeared there arose from
the rootstock a stem differing greatly in appearance, usually without
branches, and lacking the green colouring matter (_chlorophyll_). It is
pale brown in colour, of stouter build, but much shorter, for whereas
the barren stem is about two feet in length, the fertile is only a few
inches, or at most less than a foot. The leaf-sheath is longer, and the
teeth frequently adhere two or three together. The stem terminates in a
kind of cone, consisting of many whorls of flat scales, each supported
by a central stalk, on the underside of which are arranged from six to
nine capsules containing spores. These spores are very curious: they
are globular in form, and invested with several coats, the outermost of
which splits into four narrow strips, which are highly hygroscopic, and
which remain attached to the spore at one point only. These _elaters_,
as they are termed, are very sensitive to changes in the humidity
of the atmosphere, as may be proved by breathing upon them, however
slightly, when they will be seen (through the microscope) to be in
active movement. In many ferns the spores require months to elapse
before germination takes place; those of Horsetails will germinate in
a few hours. Owing to its possession of chlorophyll the spore, if not
placed in a situation suitable for germination, perishes in the course
of a few days.
The name of the genus is from the Latin, _equus_, a horse, and _seta_,
a bristle. The fertile stems appear in March and April, the barren ones
at intervals later.
=Lichens= (_Lichenes_). Plate 126.
The rambler will meet with specimens of the Lichen tribes at every
turn, when he has got fairly away from the smoke of towns. He will find
them on the tree-trunks or rocks and walls, old posts and palings,
on thatch and on the ground. Wherever they are found they may be
accepted as certificates of the purity of the air. Formerly considered
as a distinct type, they are now held by the advanced school of
cryptogamic botanists as _commensals_, or partnerships formed between
a _fungus_ and an _alga_. They are usually thin crusts, consisting
of an upper and a lower epidermis, formed of closely crowded cells,
and to the lower layer rootlike filaments are attached. Between these
layers are two differing elements; a loose stratum of green cells
(_gonidia_), which are said to be _algæ_, and below these a layer of
fungoid threads. The contention of the new school is that these _algæ_
have been captured by a fungus and held in bondage, being forced to
elaborate starch by means of their chlorophyll from the inorganic
material obtained by the rootlike filaments, which starch the fungus
is able to feed upon. Some of the green cells are pushed out from time
to time invested with a few wisps of fungus-threads, and so reproduce
the partnership. It is but right to add that some good authorities on
this branch of botany decline to accept these views, and still regard
lichens as independent organisms and not partnerships.
[Illustration: =Triangular Moss.=
Hypnum triquetrum.
=Hair-Moss.=
Polytrichum formosum.
--MUSCI.--]
[Illustration: A.--=Fly Agaric.=
Amanita muscarius.
B.--=Edible Boletus.=
Boletus edulis.
C.--=Puff-ball.=
Lycoperdum gemmatum.
D.--=Chanterelle.=
Cantharellus cibarius.
--FUNGI.--]
The species are very numerous, but their identification is not easy,
and requires serious application. The two figured are exceedingly
common in some districts. Various species of Cup-moss (_Cladonia_) will
be met on heaths, sandy hedge-banks, etc. They have a flat crust-like
base, from which arise pale grey tubes or cups, bearing at their tips
the bright scarlet, pinky-brown, or even black fruits. A more common
form in woods and on banks is _Cladonia pyxidata_, with the tube
greatly increasing in width upwards. _Cladonia rangiferina_ is the
well-known Reindeer-moss, of inestimable value in extreme Northern
latitudes as the food of the useful animal whose name it bears; it may
be found in abundance in this country on heaths and hillsides covering
the ground beneath the heather.
The other species figured in our plate, the Wall-lichen (_Physcia
parietina_), is also very common, forming the familiar orange stains
upon walls and maritime rocks. A closely allied species, the grey
_Parmelia saxatilis_, is common on tree-trunks: it has been used time
out of mind in the production of a brownish-red dye for wools. Several
others of the same genus are valuable in a similar direction: our own
_Parmelia perlata_, which grows on tree trunks, is largely imported
from the Canaries as a dye-weed, and has been sold at as high a rate as
£200 per ton.
Lichens are generally of slow growth and long life. Mr. Berkeley kept
watch upon a patch of _Lecidia geographica_ for twenty-five years,
and found little change in it all that time. The Rev. Hugh Macmillan
recounts how he found on the top of Schiehallion a species of lichen
encrusting quartz rocks, which exhibited beneath the lichen the marks
of glacial action as distinct and unchanged by atmospheric effects as
though the glacier had only passed over them yesterday. He suggests
that the lichen may reckon its days back very nearly if not quite to
the glacial period in Britain!
There are upwards of a thousand British species, and the best list of
them will be found in “Crombie’s British Museum Catalogue of Lichens,”
of which the first part was published in 1894.
=Mosses= (_Musci_). Plate 127.
Another important tribe of flowerless plants, to which we must be
content with merely giving the general characters, for in a volume
primarily intended as a guide to wild-_flowers_ we must not occupy too
much space with plants that do not produce flowers. At the same time,
we believe the non-botanical among our readers will be glad to have
a slight introduction, upon the strength of which they may cultivate
the closer acquaintance of a most beautiful and interesting group of
plants.
A. Three-cornered Hypnum (_Hypnum triquetrum_) is a common species
on woodland banks, growing in branching tufts. The stems are well
clothed with leaves, which consist of a single layer of cells; there
is therefore no necessity for the breathing pores (_stomates_) found
on the leaves of flowering plants and giving access to the tissues
beneath the cuticle. The leaves of mosses are not provided with
stomates; neither are they stalked, but attached directly to the stem
by their base. From the sides of the stem at intervals a number of
brown, hair-like threads are given off, and each of these ends in a
brown, pear-shaped nodding organ, the spore capsule. These capsules are
each closed with a lid (_operculum_), beneath which is a double row
of teeth, their tips directed towards the centre of the mouth. When
the spores are ripe the operculum is cast off, and these teeth erect
themselves to allow the minute spores to escape. The teeth (forming the
_peristome_) of mosses are always some multiple of four; in Hypnum each
row contains sixteen.
B. Beautiful Hair-moss (_Polytrichum formosum_) represents another
division of mosses in which the fruits are borne on the termination
of the stem or principal branches. In an earlier condition than
that figured the capsule is covered with a conical densely-hairy
cap (_calyptra_); this is thrown off when the spores are ripe, the
operculum follows and the spores are cast.
=Mushrooms and Toadstools= (_Fungi_). Plate 128.
We cannot pretend to do other than call the rambler’s attention to the
interesting plants that are variously called mushrooms or toadstools,
according to whether they are of the two or three species commonly
eaten, or of the multitude concerning which the British public knows
nothing, and therefore dismisses them as worthless toadstools.
A. The Fly-Agaric (_Agaricus muscarius_), though in general structure
it closely resembles the common mushroom (_Ag. campestris_), is to be
avoided as a poisonous species. Its large orange or crimson cap, more
or less thickly dotted with whitish flakes, is a very striking feature
in woods in late summer and autumn. An examination of the underside of
the cap (_pileus_) will reveal a great number of thin yellowish plates
set on edge and radiating from the stem to the circumference. Over
these plates or _gills_ is stretched a membrane, called the _hymenium_,
on which the spores are borne. From this characteristic of the bulk of
our mushrooms and toadstools the tribe containing them is dubbed the
_Hymenomycetes_.
B. Edible Boletus (_Boletus edulis_). In this group (_Polyporei_) the
hymenium, instead of investing gills, lines minute pores or tubes,
with which the under surface of the pileus is packed, and in which the
spores are produced. Many of the _Boleti_ are edible, but their good
qualities are known only to the few in this country. _Edulis_ may be
distinguished from other species by a delicate network of raised white
lines covering the stem.
C. Jewelled Puff-ball (_Lycoperdon gemmatum_). This species represents
a tribe in which the spore-bearing surface is contained within the
fungus. In a young state Puff-balls of many kinds are filled with a
white creamy substance, and so long as this remains white and does not
change colour on being cut the fungus is good to eat, after being cut
in slices and fried. When the spores are ripe the Puff-ball splits
open at the top, and discloses a hollow filled with brown dust--the
spores. Certain species of Lycoperdon attain very large proportions:
_L. giganteum_ is abundant in some localities in grassy places, usually
measuring nine or ten inches in diameter, but occasionally it exceeds
twenty inches, and weighs as many pounds. Slices may be cut from one
side of it for several days in succession, but so long as the rooting
portion is not interfered with it will continue to grow. _L. gemmatum_
is common on downs or pastures. Readers should be cautioned against
eating these small species in a raw state, as such a course has been
known to have serious effects.
D. Chanterelle (_Cantharellus cibarius_). This belongs to the same
section as the Fly-Agaric, in which the spore-bearing membrane is
spread over gills; but in _Cantharellus_ the gills are reduced to thick
ribs that run from the edge of the pileus partly down the stem. The
whole fungus is coloured with orange-yellow, internally as well as the
outside. It is often abundant in woods in summer and early autumn.
It is much esteemed for its esculent qualities; but it requires much
cooking, and should first be thrown into hot water for a few minutes,
then dried on a cloth, and fried or stewed gently.
=Small-leaved Lime= (_Tilia parvifolia_).
Several species of Lime may be met in woods and plantations, but
respecting the right of each to be called indigenous there is a good
deal of difference of opinion among authorities. Some say the present
species is a native and the Large-leaved Lime (_T. platyphyllos_)
not; others reverse this verdict and say that _platyphyllos_ is
certainly native, but that _parvifolia_ is doubtfully so. There is
little difference, other than the size of the leaves, between the two.
Both are trees of sixty feet and upwards. The leaves are alternate,
heart-shaped and toothed, lop-sided at the base, and about two and
a half inches across in _parvifolia_, compared with four inches in
_platyphyllos_. In July and August the Small-leaved Lime puts forth
her yellowy-green blossoms arranged in cymes, the long stalk of which
is furnished with a long pale-coloured bract. The flowers consist of
five sepals, five petals, a great number of stamens, a five celled
globular ovary with simple style and a five-toothed stigma. Only one of
the cells matures its two ovules, so that the fruit is two-seeded. The
flowers are sweet-scented, and very rich in honey.
The generic name, _Tilia_, is that by which the Romans knew the tree.
=Tree of the Gods= (_Ailantus glandulosa_).
This elegant shade-tree was introduced from North China in 1751,
and brought its name with it--Ailanto, or Tree of the Gods. It has,
however, been better appreciated in France and Italy than in this
country. It grows to a height of fifty or sixty feet. The leaves are
compound, pinnate, a fact that might easily be overlooked, for the
whole leaf is so large--sometimes as much as six feet in length--that
its stalk and mid-rib might well be mistaken for a branch clothed
with opposite leaves. The leaflets are toothed, and the teeth bear
glands on the lower side, whence the specific name. Its flowers, which
open in August, are borne in clusters at the end of the branches. They
are small, greenish-white in colour, and give off an evil odour. There
are two forms of flowers, the one consisting of a five-parted calyx,
five petals, and ten stamens; the other with calyx and petals the same,
but fewer stamens and three, four, or five ovaries. The flowers are not
represented in our illustration, the drawing having been made when the
tree was in fruit. These will be seen to look like small imitations of
ash-keys. It is a rapid grower in almost any soil, though it succeeds
best in a light humid earth, and appreciates a little shelter. Its
leaves are the favourite food of one of the large silk-producing moths
(_Attacus cynthia_), but most other insects disapprove of it.
[Illustration: =Small-leaved Lime.=
Tilia parvifolia.
--TILIACEÆ.--]
=Maples= (_Acer_).
Our English Maple is the Common or Small-leaved or Field Maple
(_Acer campestre_) that grows wild in hedge-rows and thickets in
England and Wales, but is only naturalized in Scotland. It is a small
spreading tree, scarcely exceeding twenty feet in height, with leaves
five-lobed, the lobes again lobed or toothed. The flowers are small,
green, in corymbs, with narrow sepals and narrower petals, succeeded
by two-winged two-seeded fruits called _samaras_; the wings being
horizontal. Flowers May and June.
The Great Maple or Sycamore (_A. pseudo-platanus_) is a tree commonly
grown in the streets, squares, and parks of London and other great
cities on account of its smoke-enduring qualities. It has been so long
established here that it is generally but erroneously regarded as a
native. It is a tree of very rapid growth, and attains a height of
about eighty feet; living upwards of two hundred years. Leaves large,
five-lobed, unequally toothed. Flowers, greenish-yellow, May and June.
Samaras large, wings diverging. Native of Mid-Europe and Western Asia.
[Illustration: =Tree of the Gods.=
Ailantus glandulosa.
--XANTHOXYLACEÆ.--]
The False Sycamore or Norway Maple (_A. platanoides_) is the species
shown in our figure. It is a native of Europe, introduced to England
in 1683. It is a considerable-sized tree, attaining a height of about
sixty feet. Its leaves are heart-shaped in outline, five-lobed, sharply
pointed, with a few large sharp teeth. The flowers appear in April and
May; bright yellow. The samaras are brown, the wings widely diverging.
Acer is the old Roman name for the Maple.
=The False Acacia= (_Robina pseudacacia_).
The False Acacia, Common Acacia, Robinia, or Locust-tree, as it is
variously styled, is a native of mountain forests in North America,
attaining its greatest perfection in Kentucky and Tennessee, where it
attains the height of ninety feet and a diameter of four feet. It has
been grown in this country for two hundred and fifty years, it being
one of the earliest trees introduced from the New World, its graceful
habit and light pinnate leaves commending it as an ornamental tree
for the plantation. In the United States it is in great repute as an
ornament, a shade or a timber-tree; it grows with great rapidity, and
its timber is of great durability, so that our cousins use it largely
for ship-building, railway sleepers, and fences. When William Cobbett
visited the States he was greatly struck with the useful nature of
this tree, and on his return to England spared no pains to make its
virtues known to his countrymen, even starting a nursery for the
purpose of supplying the young trees, and creating quite a rage for
Locust-planting for several years.
The leaves are long, compound, the leaflets being arranged in a
pinnate manner, with an odd leaflet. The stipules are in the form of
prickles at the base of the leaf-stalk. It is a leguminous plant,
and its flowers greatly resemble those of the pea. They are white,
sweet-scented, and gathered into a long, pendulous raceme, like that
of the laburnum: May and June. The tree is sensitive, and on a branch
being touched the leaves will all incline towards the branch, whilst
each leaflet advances half-way towards its opposite fellow. The same
movements occur at sunset, the leaflets then remaining folded face to
face until dawn. The fruit (shown in figure) is that form of pod called
a _lomentum_, in which the valves are constricted between the seeds.
[Illustration: =False Sycamore.=
Acer platanoides.
--SAPINDACEÆ.--]
The genus is named in honour of Jean Robin, a French botanist, whose
son cultivated the first specimens of _R. pseudacacia_ in Europe.
=The Ash= (_Fraxinus excelsior_).
One of the most pleasing in growth of our forest trees is the Ash,
its grey trunk rising to eighty or a hundred feet, and its sweeping
branches, the lower ones bending upwards at the tips, clothed with the
gracefully curving long pinnate leaves. The character of these compound
leaves and their leaflets is well shown in our illustration, together
with two clusters of the winged fruits.
The Ash is a native of Britain, although most of the specimens we meet
in woods and plantations have been reared in a nursery and planted
out. There are many cultivated varieties of _F. excelsior_; and a
large number of species have been introduced during the present and
last centuries, chiefly from S. Europe and N. America. Ash and Privet
are the only native representatives of the order Oleaceæ, to which
the Olive belongs. It cannot be said that _Fraxinus excelsior_ is a
typical representative of the order, since most species included in it
bear flowers composed of all the floral organs, whereas _excelsior_
has neither calyx nor corolla. Its flowers appear in April or May,
and are of three kinds:--staminate, consisting of two dark purple
stamens only; pistillate, consisting of an oblong ovary with short
style and cleft stigma; hermaphrodite, consisting of ovary and two
anthers with very short filaments. These flowers are individually small
and inconspicuous, but associated as they are in dense panicles from
the new wood formed in the previous season, and appearing before the
black leaf-buds have burst; they are collectively very conspicuous.
The leaves are very late in making their appearance, as they are among
the first to fall after the early frosts of autumn. The “keys,” as the
fruits are called, each contain two seeds, and the wing has a twist
which causes the key to spin rapidly when the breeze separates it from
the bunch and carries it far from the parent tree.
[Illustration: =False Acacia=.
Robinia pseudacacia.
--LEGUMINOSÆ.--]
=The Black Mulberry= (_Morus nigra_).
It may surprise some of our readers to learn that the Mulberry-tree is
not a native, though it is a familiar object in old gardens and parks.
It is generally stated that the first Mulberry-trees were introduced
in 1548 and planted at Syon House, Isleworth (then the Convent of St.
Bridget of Zion), but the Duke of Northumberland is credited with
saying early in the present century that he could then trace them back
quite three hundred years. Several of this batch are still living,
and one--probably the finest old Mulberry in England--is a hale and
vigorous ornament to Mr. George Manville Fenn’s lawn at Syon Lodge. Mr.
Leo Grindon is of opinion that the tree was originally introduced by
the Romans, for he finds that the Saxons had a name for it, which would
probably not have been the case had it not been growing in their midst.