ILLUSTRATIONS OF INDIAN BOTANY.
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the spines. Other genera of this small order are even more inexplicable than this, unless examined at a similarly early stage of their development. These I pass unnoticed, not being- Indian plants.
Character of the Order. Calyx equally 5-lobed. Corolla monopetalous, hypogynous, irregular, throat ventricose, limb bilabiate, the limb subvalvate in aestivation. Disk hypogynous, fleshy, or sometimes glandular. Stamens included within the tube, didynamous, with the rudiment of a fifth. Anthers adnate, 2-celled; connective articulated with the filament, slightly prolonged beyond the cells, glandular at the point. Ovary seated on a glandular disk, formed of 2 carpellary leaves, anterior and posterior as regards the axis, at first 1-celled afterwards divided into 2-4 or 6 spurious cells. Style 1, simple, stigma bilamellate. Fruit capsular or drupaceous, dehiscent or indehiscent, few- or many-seeded ; seed (in Sesamum attached to an easily separable, 4-sided, central placenta) winged or wingless, exalbuminous, embryo straight ; cotyledons plano-convex, longer than the radicle. Herbaceous plants, often with soft texture and heavy smell, covered with glandular hairs or quaternary vesicles. Leaves opposite or alternate, undi- vided or lobed, without stipules. Flowers axillary, solitary or clustered, usually large, furnished, in many cases, with conspicuous bracts, sometimes with glands on the pedicels.
Affinities. These plants seem closely allied to Bignoniacece, a point on which all Botanists appear to be agreed. Lindley remarks that the only real differences that can be found between them and Bignonals consist in their parietal placenta?, their wingless or nearly wing-less seeds, which in most cases are definite, and sometimes in their woody lobed placentae, which spread and divide variously in the inside of the pericarp, so as to produce an apparently 4- or 6-celled fruit, out of a 1-celled ovary. He further well remarks, "It is not a little remarkable that such observers as De Candolle (Prod. 8. 249) and Endlicher, (Linncea 7. 8) should suppose the fruit of this order, to be formed out of 5 or 4 carpels, a statement entirely opposed to both theory and fact, it being really composed of an anterior and posterior carpel, exactly as that of the other orders of this present Alliance." As regards the alleged difference of placentation, the case is not clearly made out ; on the contrary, I am disposed to view the placentation as nearly, if not quite, similar in kind in both orders, and as regards the seed, the genus Sesamopteris is separated from Sesamum, mainly on that character, "semena compressa ala rnembrancea cineta, 1 ' DC. The differences, therefore, between the two orders seem to be very slight ; habit having, apparently, as much to do with their separation as structure.
Geographical Distribution. The few species appertaining to this order, about 25 or 30, are all tropical or sub-tropical, but very widely diffused over the world. In Africa they are most numerous, but America, Asia, and Australia all have their species ; five or six are natives of India.
Properties and Uses. The gingilie oil of India is obtained from the seed of Sesamum Indicum, and is in general use among the natives, when fresh, as an eating oil. The leaves of S. prostratum and Pedalium murese, render water in which they are agitated thick and mucilaginous, and are therefore in some repute as demulcents and refrigerants in ardor urinae.
Remarks on Genera and Species. The only species on which I can venture to offer any remark is Ses. prostratum. Of this plant Pluknet published a very good figure in 1705, upwards of 140 years ago, but, of course, at that time, it was imperfectly described. In 1774 Retz pub- lished a good character and description, quoting Pluknet's figure. In 1800 Willdenow reduced it, curtly remarking : "S. prostratum, Retz, est planta mihi valde clubia, convenit enimpluribus notis cum Torenia Asiatica? (! !) It thence remained unacknowledged until 1821, when Roth restored it to its place in the genus ; and in 1825 Sprengel confirmed his opinion by adopting it and admitting the species into his system of plants. Such being the case, it was with considerable surprise I found it thus entered in DC.'s Prod, in 1845 : "Sesamum prostratum* Retz,=ex Willd. (sed negante, Roth.) Torenia Asiatica." This species is not uncommon on the sands behind the beach at Madras, and along the coast there. It lies flat on the ground, is very hirsute,
