Page:Illustrations of Indian Botany, Vol. 1.djvu/111

This page has been proofread, but needs to be validated.
ILLUSTRATIONS OF INDIAN BOTANY.
43

as wide a range: D. pelata I have only found on the higher hills, but on these, both on the continent and in Ceylon: D. intermedia is a European plant, but the specimen figured in the accompanying plate was procured from an Indian herbarium, but whether a native specimen or not is unknown.

Properties and Uses. These plants were formerly esteemed by alchymists, on account of the drops of pellucid dew, which they support on the glandular points of their hairs, to which they gave the name of Ros solis, whence the name Sun-dew which they now bear. They are inodorous, but somewhat acid and acrid. Bruised with salt and applied to the skin, they are said to blister it: mixed with milk they curdle it; probably through their acidity: cattle refuse them, hence they are, apparently with much justice, supposed to be poisonous or otherwise injurious to them. Drosera peltata, which becomes nearly black in drying, tinges the paper in which it is kept a beautiful pink colour, and might probably as Mr. Royle suggests, afford a valuable dye. The whole of these plants are remarkable for their property of contracting on such insects, as happen to light on their leaves, but none of them to the same extent as those of Dionoea muscipula, (Venus' fly trap) which on some hairs in the middle of the lobes of the leaf being touched, immediately contract with great rapidity on whatever object may have excited them, but so long as these hairs are avoided, the surface of the leaf may be freely touched without exciting contraction.

Sub-ord. PARNASSIEAE.

The place the genus Parnassia ought to occupy in the natural arrangement of plants, has long been a subject of doubt among Botanists. Jussieu placed it along with Drosera and Resida, at the end of the Capparideae as allied genera, being principally influenced in this decision by the parietal placentation. Since then both Drosera and Resida have been made the types of distinct orders, but the place of Parnassia still remains undetermined. DeCandolle refers it with doubt to Droseraceae, Dr. Lindley to Saxifrageae, notwithstanding its circinate vernation, considering the nectarial scales as "a peculiar development of an hypogynous disk, which assumes the form of 5 fringed scales alternate with the stamens, and of highly curious structure." Bartling (Ordinus Naturalis Plantarum) thinks it more appropriately placed among the Tamariscineae, while Dr. Arnott, in my opinion, with greater justice, considers it a sub-order of Droseraceae, and here accordingly I have kept it for the present, though it differs from both orders, in the want of albumen in the seeds, and from Droseraceae in the want of glandular pairs on the leaves. The following character of the sub-order was drawn up by Mr. Arnot and published in our Prodromus.

Sub-order. Parnassieae (Arn.) Sepals 5; oestivation imbricative. Petals 5, alternate with the sepals, hypogynous. Stamens hypogynous, 10— 20, some of them often sterile : anthers bilocular, bursting longitudinally. Ovary solitary, unilocular : style none, and four sessile stigmas opposite the placentae; or one with a lobed stigma. Fruit a capsule, 1-celled, 4-5, valved and loculicide; or indehiscent, and then the placentae is only at the base. Seeds numerous. Albumen O. Embryo erect, or the radical pointing to the hilum. Bog plants. Leaves nearly all radical, without glandular hairs.

Geographical Distribution. The species of this genus are widely distributed, being met with in every country of Europe, North America, and on the higher hills of both the north and south of India; always in boggy marshy places. The three species figured here are respectively from the Pulney mountains, (P. mysorensis), the Neilgherries, (P. Wightiana), and from the Himalayas, (P. nubicola).

Properties and Uses. Of the properties of this order little is known, the P. palustris, when fresh, is somewhat bitter, which it loses by drying, the infusion is also said to be rough and astringent to the taste, and strikes a deep red colour on being mixed with sulphate of iron. In the northern parts of Europe and Siberia, the decoction is a popular remedy for retentions of urine and calculus disorders.