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Page:Illustrations of Indian Botany, Vol. 1.djvu/51

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ILLUSTRATIONS OF INDIAN BOTANY.


ANONACEACE.

This large, and truly tropical, order, is composed entirely of trees or shrubs, (no herbaceous member has as yet been found appertaining to it) with alternate, simple, entire, ex-stipulate, often fragrant, leaves ; and hermaphrodite, except in Hyalostemma, (Wall.) regular, axillary flowers. These are usually pale, or dull yellowish green, or brown, but sometimes yellow, and in Uvaria grandijlora are rich crimson, for the most part axillary, solitary, or a few together; but in Guatteria longifolia they form large clusters; in Artabotris, they spring from curiously hooked grapples, or tendrils, apparently abortive branches.

The calyx is generally deeply three parted; or rather perhaps, consists of three distinct sepals, partly united at the base; where they are very broad. The corolla consists of six petals, in a double series, three and three, often unequal; sometimes the exterior, sometimes the interior series, being much larger than the others; all caducous. The stamens are usually very numerous, sessile, and closely cover the whole of the enlarged, somewhat globose torus, rarely definite as in Bocagea : the anthers are two-celled, lateral, opening outwardly, and surmounted by an elongation of the connective, sometimes pointed, but oftener flattened, and truncated, more rarely they are adnate, as in Milium, a peculiarity which, when it occurs, promises to afford a useful generic distinction. The ovaries are generally numerous, one-celled, congested on the apex of the prominent torus, either free or united : ovules few or numerous, variously attached; being either numerous and transverse, springing in a double row from the inner angle of the cell in Uvaria; or solitary, and erect, and from the bottom of the cell in Guatteria; or pendulous from the top of the cell in Orophea. Style usually short or wanting, stigma capitate. The fruit is apparently more variable in its character than the other parts of the fructification, and has hitherto been almost entirely looked to for generic distinctions. In some, it consists of numerous, united, one-seeded, carpels, enveloped in soft pulp, and forming together a pulpy fruit, as in Anona; (the custard-apple, sour sop, and bullock's heart) in others, the cai-pels have one or several seeds, and are borne on along peduncle, as in Uvaria, Guatteria, Sec. and sometimes these carpels though otherwise distinct, remain sessile, or with the peduncles so short that the carpels form together a globose head : (this variation occurs in some species of Uvaria, and Miliusa.) In others, as Unona, the carpels are elongated, containing several seeds, and contracted between them like a necklace of beads. The seeds universally possess the remarkable character of having ruminated albumen, like those of the nutmeg. A few have them arilled as in that genus, which (aril) when it exists, is supposed to secrete at the base of the seeds, a resinous highly aromatic matter. This is the case in what is called the Ethiopian pepper, ( Habzelia Ethiopica J and some others, which, partly on that account, the younger DeCandolle has united to form the genus Habzelia, a genus common to both Africa, and America, but not yet found in Asia.

Affinities. The affinities of Anonacece are so various, as not to be easily indicated in a few words, but their closest alliance is certainly with Magnoliacece, from which however, they are readily distinguished, by their ex-stipulate leaves, their more distinctly formed, and sub-persistent calyx, by the form of their anthers, the arrangement of their ovaries, but above all by their ruminated albumen, This last character however, combined with the ternary arrangement of their flowers, the occasional presence of an aril, and their aromatic properties, so closely associates them with Myrslicacece, (the nutmeg tribe) that Professor Lindley seems to consider the latter, as little ehe than an apetalous form of Anonacece. Thus constituted, it is difficult to give an abridged character of the order, but as, generally speaking, the Indian species present the normal forms, their character may be summed up in the following terms.

Essential Character. Polypetalous, polyandrous, ovaries wholly superior : carpels more or less distinct : very rarely solitary : seeds, usually without an aril, albumen aromatic, ruminated. Leaves alternate, ex-stipulate. In one Indian genus ( Hyalostemma J the flowers are diaecious.

Geographical Distribution. This, as already remarked, is strictly speaking, a tropical order, confined to Asia, Africa, and America, none having as yet been found in Europe, or Austra-