Page:Illustrations of Indian Botany, Vol. 2.djvu/115

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ILLUSTRATIONS OF INDIAN BOTANY.

53

ed portion cohering with the middle vein of the lamina : aestivation somewhat imbricate, rarely valvate. Stamens 5, alternate with the petals, distinct, folded back during aestivation, anthers ovate, 2 celled, dehiscing longitudinally. Ovarium cohering entirely and closely with the calyx, erowned by a flashy disc (an expansion of the torus) 2-celled : ovules solitary, pendulous : styles 2, simple, their bases more or less thickened and fleshy (stylopodia), covering the disc and top of the ovary : stigmas simple. Fruit dry (a cremocarpium) consisting of two carpels (or mericarpia) which adhere by their face (commissure,) to a common axis (carpophorum), but in maturity separate from it, and are pendulous : each mericarp indehiscent, traversed by 5 longitudinal primary ridges (iuga primaria), one opposite to each petal and each stamen and often also by alternating secondary ones (juga secondaria), the ridges being separated by channels or interstices. In the substance of the pericarp are linear ducts or canals (vitta) full of an oily or resinous matter, these are usually lodged in the interstices, sometimes below the ridges, rarely wanting. Seed pendulous, usually cohering with the carpel, rarely loose. Embryo minute, at the base (that is, at the apex of the fruit) of a copious horny albumen : radicle superior, pointing to the hilum. Herbaceous or rarely suffYutescent plants : stems usually fistular and furrowed. Leaves alternate, very rarely opposite, simple (without articulations), variously cut, sometimes reduced to the petiole (phyllodium). Flowers in umbels, the umbel sometimes capitate, usually with an involucre."

Affinities. These are not of easy determination and are 1 think still to be discovered. If we attempt to determine their affinities by their floral arrangement and general habit they come well after Satifrageae, but if we look principally to the ovary and seed for ordinal characters their affinity with that ord^r is remote, while with Ampelideae, through Araliaceae they become closely approximated. Ranunculaceae by agreeing in the highly albumenous seed and in general habit are also allied both directly, through Ranunculus and Thalietrum on the one side, and Pimpinella, Scandex, &c. on the other, and indirectly through Clematis and Aralea which have many points of resemblance. The affinity between these two orders is strongly insisted on by Lindley who observes, " if we consider fairly the respective organization of Ranunculaceae and Umbelliferae especially of such gsnera as Thalietrum in the one and Pimpenella in the other, we shall find that no positive mark of discrimination between them can be pointed out, except the superior carpels of the former and the inferior ones of the latter ; for the indefinite stamens of Ranunculaceae are no longer capable of forming a distinctive character since the discovery of Casalea. As for Thalietrum faeniculaceum any one would take it for an umbelliferous plant without attentive observation. Now it is impossible to acknowledge any system to be natural in which, under these circumstances of almost identity of structure and sensible properties two such orders are disjoined ; and 1 consider the restoration of Umbelliferae and Ranunculaceae to their relative positions one of the strongest arguments in favour of the necessity of this albumenous group."

I quote this passage not for the purpose of opposing the views of the author, though I do not altogether adopt them, but in confirmation of my remarks under Cacteae and as showing that Dr. Lindley by adopting and acting on the opinion that " no division of Exogens has been discovered more in accordance with natural affiiities than that which depends on the different degree of development of the flower" while he in his first by group employing one altogether at variance with its principles has thereby produced associations equally if not more unnatural than those which he proposes to remedy and forms a system greatly inferior to them in facility of application to practice. By this mixing of systems there are no fewer than 175 orders interposed between Umbelliferae and Rubiaceae (Cinchonaceae Lind.) and 177 between it and Capiifoliaceae though in both these we find the copious albumen of his Albumenous group and in the latter occasionally polypetalous flowers. Looking therefore to the primary structure, that of the seed, and to the epigyno'us flowers of these two orders, I cannot but think the affinity between them and Umbelliferae is much closer than between it and some of the other alliances associated in his group Albumenosae. Had the principle been adopted, of associating as a class all the orders distinguished by having highly albumenous seed, to be afterwards divided into subclasses according to the flowers, we should not have had to complain of the incongruity of assigning to two sets of organs wholly incompable with each other, high values in one place and very low ones in another. Many instances of this could be adduced hat