FIG-TREES OF NEW CALEDONIA.

39

measure sometimes about twenty-two feet in diameter at the base. The trunk is augmented by ligneous ribs as far as twenty feet from the ground, and these "sometimes separate from the trunk at a height of eight feet, and are transformed into cylindrical roots two feet thick. The tree looks as if it were supported by buttresses. This scaffolding, however, does not penetrate very deep into the earth." *

Forster notices a still more remarkable circumstance in the fig-trees of New Caledonia. "The inhabitants," he says, "were commonly seated at the foot of these trees, which had this remarkable quality, that they shot long roots from the upper part of the stem, perfectly round, as if they had been made by a turner, into the ground ten, fifteen, and twenty feet from the tree, and formed a most exact straight line, being extremely elastic, and as tense as a bow-string prepared for action." +

I shall conclude this part of our subject by mentioning two more instances of the intermediate stem from Stedman and Dampier. The former gives a figure of a tree found in Surinam, called the Matakee tree, whose roots, he says, "spread above ground in such a manner that they will conceal a score of men from each other;" and he farther mentions that a man on horseback can ride through the interstices; and that a table large enough to *Humboldt's Pers. Nar. vol. iv. p. 95.

↑ Forster's Cook's Voyages, vol. ii. p. 392.

dine twelve persons, may be substituted from one single piece.*

Dampier, in the first volume of his voyages, describes the red mangrove as growing by the seaside, or by rivers and creeks, and always "out of many roots about the bigness of a man's leg, some bigger, some less, which, at about six, eight, or ten feet above the ground, join into one trunk or body, that seems to be supported by so many artificial stakes. Where this sort of tree grows, it is impossible to march by reason of these stalks, which grow so mixed one among another, that I have, when forced to go through them, gone half a mile, and never set my foot on the ground, stepping from root to root."

Linnæus used the word TRUNCUS (trunk) as a generical term for all stems; and under it he arranged the seven following species :

1. CAULIS, the Stalk.

2. CULMUS, the Culm, or Straw. 8. SCAPUS, the Scape.

4. PEDUNCULUS, the Peduncle.

5. PETIOLUS, the Petiole.

6. FRONS, the Frond.

7. STIPES, the Stipe.

The peduncle, or flower-stalk, however, and the petiole or leaf-stalk, are to be considered as only parts of the stem; the term frond is limited to the palms, and to the ferns, mosses, and other crypto

* Stedman's Surinam, vol. ii. p. 188.

DEFINITIONS OF TREES AND SHRUBS.

41

gamic plants; and that of stipe, is confined to ferns and fungi.

Before considering the different species of stem, it will be proper to advert to the distinction of plants into trees, shrubs, under-shrubs, and herbs.

The term tree requires no definition; it is designated in Botany by its Latin name arbor, a tree, arbores, trees. The stem of certain plants, which, though not trees, yet resemble them in habit, is named a tree-like stem (CAULIS arboreus); or, if it be first herbaceous, and become woody by age, it is called an arborescent stem (CAULIS arborescens); and the similarity which some shrubs and herbs bear to trees supplies not unfrequently a very characteristic name for them. Hence, we have Erica arborea, tree-heath; Lavatera arborea, seatree-mallow; Dianthus arboreus, tree-pink, &c.

It might be thought easy to lay down such a definition as would clearly distinguish a tree and shrub from each other; and yet this is perhaps impossible. At one period Linnæus thought that buds were produced by trees, but not by shrubs; and that by this circumstance they might be discriminated, but he did not long retain this opinion, and indeed the truth is that some shrubs do produce buds, and that trees in hot countries do not. The definition of the shrub, as given in Martyn's Language of Botany, is perhaps as expressive as any we have. It is this: "In its general accept

woody stems, dividing from the bottom, more slender, and low than in trees." The Latin frutex, a shrub, frutices, shrubs, form its botanical appellations.

Next is the Suffrutex, or under-shrub; and one unacquainted with botanical nomenclature would suppose that there could be little difficulty in conceiving the meaning of this term. It means, he would say, "a shrub of small size," "a shrub lower than shrubs usually are;" but he would be mistaken, for the term has no reference to magnitude.

There is a very pretty plant, which in spring and part of the summer adorns with corymbs of purplish, white, and flesh-coloured flowers, the cliffs of Gibraltar; and is named Gibraltar Candytuft (Iberis Gibraltarica). Before the winter months come on, its flowers, leaves, and even its stems, have disappeared; they have dried up and are gone. But, on examination, it will be found that the root remains; that it is woody; that the bottoms of the stems also remain; and that they too are woody. The stems that have vanished were not, however, of ligneous texture; — they were herbaceous, and, like annual plants, perished when their flowering was over. But the woody root and stumps are perennial, and on the return of spring they throw out new herbaceous flowering stems, which again die before winter, and this process goes on year after year for an indefinite period. Now this is an example of

FAMILIES OF PLANTS.

43

an under-shrub, which, as is well expressed in a late work, is a plant "the lower part only of whose stems is woody, but whose upper part being of an herbaceous nature, dies every year."

By the term herb, Linnæus meant all the part of a vegetable above the root. In common language it serves to express all plants, with the exception of trees and shrubs; but it is better, with Linnæus, to consider the whole vegetable world as consisting of the following seven great families:

1. FUNGI.

2. ALGE, including sea-weeds, lichens, &c. 3. Musci, mosses.

4. FILICES, ferns.

5. GRAMINA, grasses.

6. PALME, palms.

7. PLANTE, all vegetables not comprehended in any of the preceding families.

The first species of trunk we shall attend to is the CAULIS, stem, or stalk, which is derived from the Greek xauλos (kaulos), the trunk of a tree, but in Latin it meant the stalk of an herb only. From it our words cauliflower and colewort are derived.

WITH RESPECT TO CONSISTENCE,

Stems may be woody; succulent or fleshy; medullary or empty.

1 CAULIS ligneus, or solidus.

* Elements of the Philosophy of Plants, by Decandolle