Page:Illustrations of Indian Botany, Vol. 2.djvu/91

ILLUSTRATIONS OF INDIAN BOTANY.

41 class, of sufficient magnitude too, to admit of its being further distributed either circularly or otherwise according to the taste or abilities of the expounder. Unfortunately the author, (Lindley) not seeing the true value of this bond of union, has, in his second edition, changed the arrangement much for the worse. Von Martius places Chenopodiaceae, JYyctagineae, &c. &c, in one group — A mar antaceae, and Paronycheae, in a second and Caryophylleae, and Portulaceae, in a third — Lindley in his second Edition has Ficoideae in one group — Portulaceae, Silenaceae, and Alsinaceae, {Caryophylleae, of other authors) and lllecebreae, in a second — and at a great distance Jlmar antaceae, Chenopodiaceae, and several genera referred by all other authors to Portulaceae, or Ficoideae, in a third.

These examples are I presume sufficient to establish the intimate relationship existing among all the plants possessing this structure, and the impossibility of ever devising a satisfactory distribution of the genera ipto natural orders that does not set out from that point.

The three orders above named, being united by this structure and being the only ones appertaining to the class Calycifiorae, I have, in conformity with these views, thought it the most judicious course to group them together as a sub class or large order and then redistribute the Indian genera into sub orders ; leaving for future consideration the final determination of all the orders into which the group ought to be divided, and the station which it ought to occupy in the system of plants. To attempt more than this would be inconsistent with the plan of this work, which does not profess to offer a new arrangement but merely to illustrate that in use, indicating from time to time, as opportunities offer, those points which appear to me defective and how they may be amended.

This as now understood by both Meisner and Endlicher is a large and apparently polymorphous order, including several tribes the affinities of which seem rather remote. Both these authors place here, not only the plants referred by us to Ficoideae, but also the genus Mollvgo. This seems a questionable association, though for the present I adopt it, as the true Portulaceae, have a central basilar placenta (the seed attached to the bottom of the solitary cell of the capsule) : but in Mollugo and Glinus excluding G. trianthimoides) the capsule has several cells with numerous seed, attached the whole length of the axis ; having besides, a five not two sepaled calyx and b^ing destitute of proper petals. This case supplies another example of the necessity of viewing the whole of those genera, having the peculiar curvembryose seed of this tribe, as belonging to one great natural family or class and re-distributing them, without reference to what has been already done, according as they can be most naturally grouped into sub classes or alliances, duly bearing in mind, that the order or class is as it comes from nature's hand a truly natural group and that the object in view is merely to distribute its contents in the most easy and convenient order. Until this course is adopted, it seems most improbable we shall ever have then disposed in such a series as will give general satisfaction. But before this can be done, the whole must be carefully re-examined. In the mean while as I can see no sufficient reason for altogether rejecting the views of these authors, though I confess I cannot fully agree with either, I shall modify the arrangement of our Prodromus by bringing Sesuvium from Ficoideae, where it does not associate well with Mesembryanthemum, to Portulaceae ; and Glinus, our only other genus of Ficoideae, being much less entitled to a place there than even Sesuvium I also remove and place with Mollugo in a distinct section, which may then be given to Paronychiaceae as better agreeing with it, both in habit and in characters, than with Portulaceae. In this way, the order Ficoideae is removed from the Indian Flora, and justly, so far as these two genera are concerned, as it is clear that Sesuvium cannot be separated from Trianthema as an order, and neither it nor Glinus can very well keep Mesembryanthemum company. Let us attempt to distribute the Indian genera according to these views.

The Indian mrvembryate genera referable to DeCandolle's class Calyajiorae, are nine in. number and may be thus distributed.

Portulaceae, — Calyx 2 parted. Corolla 4-5 petaled exceeding the calyx, conspicuous. Capsule one-celled, circumscissile, or opening by valves : placenta central in the base of the cell, seed attached by distinct podosperms. — Succulent herbaceous plants. Portulaca, Talinum,