Page:Illustrations of Indian Botany, Vol. 1.djvu/382

190 suborders Mimoseae and Caesalpineae. The former of these form a single tribe, Mimoseae the latter, is divided into three tribes, namely, Geoffreae, Cassieae and Detarieae. One species only of the first of these tribes is found in India, (the earth nut Arachis hypogea) and the third is altogether unknown here.

After this explanation I presume there can be no difficulty in understanding the table, which I prefer giving in the original Latin, after adding with, reference to the characters of the tribes, that "folia cirrhosa" alludes to the tendrils with which the leaves of many, the common garden pea for example, are furnished, and "folia primordea" to the first pair of leaves above the seed lobes, not to the seed lobes themselves, which might sometimes be mistaken for primordeal leaves in the Phyllolobeae tribes, as they ascend during germination and expand into leaf-like bodies. The cotyledons of Sarcolobeae rarely ascend in germination, and then can scarcely be mistaken for leaves owing to their thickness. It is to this section alone that characters taken from this organ are required, and even here, viewed as a means of assisting in the discrimination of genera, seem to be of little use, though, in a physiological point of view the peculiarity of alternate primordial leaves seems curious, as being confined to that tribe having tendril bearing leaves.

We now proceed to consider in succession the several suborders — commencing with the principal, both as to its extent and importance to mankind, namely.

Suborder—.

This large suborder, which is scattered in greater or less profusion over every part of the known world, is composed of herbaceous plants, shrubs and trees. The leaves are usually alternate, unequally pinnate, or if abruptly pinnate, the rachis frequently terminating in a tendril in place of the odd leaflet, or they are digitate, or ternate or simple, from the abortion of the lateral leaflets, and occasionally though rarely, the leaf itself is altogether abortive and changed into a tendril, the large stipules then performing its functions, as in Lathyrus aphaca. Stipules lateral. Flowers bisexual, or, occasionally by abortion, unisexual, racemose, spiked, capitate, or panicled, pedicels bi-bracteolate. Calyx free, 5-cleft, lobes usually unequal, the two superior ones often cohering into an upper lip, the three inferior ones more or less united, forming the lower one. Torus expanded into a lamina covering the bottom of the calyx. Petals 5, very unequal, alternate, with lobes of the calyx unguiculate — the upper one, (vixillum) larger and overlapping (he others in aestivation: the lateral ones (alae) usually unequal sided, the two lower ones often cohering nearly their whole length into one boat-shaped petal with a double claw, (carina) but sometimes altogether distinct. Stamens inserted with the petals, double their number, rarely all free, often all united into a tube surrounding the ovary, or, with 9 co- hering, and the upper one, that next the axis, free, hence diadelphous (nine and one $9⁄1$ ) the more usual form : but sometimes they are equally diadelphous $5⁄5$, rarely tri-adelphous : the filaments distinct and subulate at the apex, anthers erect, 2-celled, sometimes by abortion 1-celled, ovary solitary, free, opposite the inferior lobe of the calyx, one or many-ovuled, ovules attached to the posterior suture, style one, stigma simple. Fruit, a legume, longitudinally 2-valved, 1-celled, or spuriously 2 celled, sometimes with contractions between the seed, or with trans- verse divisions separating at maturely into so many 1 -seeded indehiscent cells, forming what is called a 'lomentum' (see plate 79). Perecarp usually double, fleshy externally, interiorly membranaceous or parchment-like. Seeds definite or indefinite, superposed, attached alternately to the valves, sometimes with a large carunculus or imperfect arillus, the hilum marginal some- times elongated. Cotyledons thin and foliaceous, ascending above the soil during germination, or thick and fleshy remaining below.

Tribe 1. —Stamens distinct. Legume not jointed, frequently contracted between the seed. Cotyledons foliaceous during germination, suffruticose, or shrubby, rarely trees : leaves simple, ternate, or pinnate.

The Indian flora presents but few examples of this tribe Sophora, Vigilia, and Edwardia, (which I have recently found on the Balaghaut mountains) being the only ones known in the Peninsula. I do not find any useful properties assigned to the plants of this tribe.