Page:Illustrations of Indian Botany, Vol. 2.djvu/228

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118

ILLUSTRATIONS OF INDIAN BOTANY.


VACCINIUM.

Calyx adherent, limb 4-5-lobed. Corolla tubular, 4-5-cleft. Stamens 8-10, epigynous, anthers adnate, 2-celled, often furnished with 2 bristles on the back, the cells ending in a tube open at the apex. Ovary 4-5-celled, placentas ascending, usually bearing the ovules on the margin. Berry 4-5-celled, often spuriously 10-celled, through the adherence of the walls to the thickened placentas. Seed several in each cell, testa coriaceous or somewhat bony : albumen fleshy: embryo orthotropous, radicle next the hilum. Trees, shrubs, &c.

According to this character, it is of no moment whether the lobes of the calyx are large or small, whether the corolla is long or short, thick or thin: the anthers may or may not be bristled, but are always expected to have the cells more or less prolonged into tubes, and to have the number of cells of the ovary equal to those of the lobes of the calyx and corolla, with, more or less distinctly, free ascending placentas and a plurality of ovules. Such is the genus Vaccinium, as understood by me, when naming the following and several other still un- published species in my Herbarium.

Dunal, in his monograph of the order Vacciniacece, retains Agapetes and Thibaudia ; End- licher, Miesner and Lindley unite them. Kunth is followed by Miesner, in expressing a doubt as to whether Ceratostema is distinct from Thibaudia, and Hooker states that he "cannot understand what are the essential distinguishing marks between them." Among the following are species which have been referred by different Botanists to Ceratostema, Agapetes, Thi- baudia, Gaylussacia and Vaccinium. To determine among so many genera, it became indispensable to examine the characters of all with much care. After the closest scrutiny and careful dissection of the flowers of all the Indian species in my collection, side by side with several acknowledged Vaccinia from both America and Europe, I found it utterly impossible, from the characters given, to make out more than one genus among the Asiatic ones, the structure being the same in all. By Roxburgh these would, perhaps, have been all referred to Ceratostema: Wallich refers them to Thibaudia, while Don and Dunal form the genus Agapetes for their reception. Had long tubular flowers been a constant feature, I might on that account, aided by geographical distribution, have followed these authors, and, assuming that as its essential character, kept up their genus. This, however, is far from being the case, and is therefore, as a generic character, useless. And on turning to DunaPs character of Vaccinium, I find the corolla described as "campanulata, urceolata vel cylindrical

In all the Indian ones it is either urceolate or cylindrical. He describes the stamens as "limbo calycis inserta," which is the case in all the Indian ones I have examined, and the fruit "Bacca calyce vestita globosa 4 aut 5 locularis loculis polyspermis, rarissime 10 locularis loculis monospermis" which, except the last clause, is equally applicable to the fruit of all I have had an opportunity of examining. The ovary, unfortunately, is not referred to in the character of either genus. The concluding clause of the character may, perhaps, account for Professor Lindley's referring one of the species to Gaylussacia, which, while that clause remains as part of the character of Vaccinium, seems scarcely a distinct genus, the fruit having 10 cells with 1 seed in each being its essentially distinguishing mark. In all other points DunaPs characters of the 2 genera are nearly word for word the same, and the abortion of all the ovules but 2 in each of the 5 cells converts Vaccinium into Gaylussacia and, unless care is bestowed in the examination, even that is not necessary, as a transverse section of a nearly mature fruit almost always presents the appearance of 10 cells with one seed in each, and I feel nearly certain that an examination of the ovary will show that but few of Dunal's 29 species have it 10-celled with a single ovule in each. G. dependens, an authentic specimen of which was most obligingly communicated to me by Mr. Gardner of Ceylon, has a 4-celled ovary, with numerous ovules, and is in fact a species of Vaccinium with very short anther tubes.

Whether Ceratostema can be kept distinct I am unable to say, but judging from the really essential points of the character, apart from the numerous non-essential ones introduced by Dunal, I think not. Thibaudia has one good distinguishing mark in the union of the filaments between themselves, and their attachment to the base of the corolla. But if that is to be taken