480 NA'IURAL HISTORY OF PLANTS. 



cate, descendent, sunnoTinted by a large woody wing, at the top of 

 whicli is the point of attachment, and traversed longitudinally by the 

 raphe. In the lower part these seeds are dilated to a small chamber 

 containing a large fleshy embryo, with a short nearly transverse 

 radicle, and thick cotyledons, more or less united to the fleshy 

 albumen surrounding them. There is only one species of this genus, 

 8. Mahogoni^ better known under the name of mahogany. It is a 

 beautiful tree from the Antilles and the neighbouring parts of the 

 main land. The leaves are alternate, usually paripinnate, with 

 folioles often opposite, petiolulate, unsymmetrical at the base. Its 

 flowers are collected, in the axil s of the leaves and at the summit of 

 the branches, into more or less ramified clusters of cymes. 



Soymida, an Indian tree, differs from Swietenia only by its thicker 

 and shorter disk, by the denticulation of the tube of the androceum, 

 which, instead of being simple, is bifid, and by the wing of the 

 seeds, which, instead of being confined to the upper part, is prolonged 

 above and below them. Khaya, a large tree from Senegal, is as 

 closely allied ; but its flowers are tetramerous. The tongues of its 

 staminal tube are equal in number to the large, petaloid, and con- 

 volute anthers ; and its capsule, like that of Soymida, opens above , 

 and below to allow the seeds, edged all round by a short wing, to . 

 escape. In this series are also ranged Chickrassia^ Indian trees, 

 whose 4-5-partite flowers have a calyx with very short teeth, and a 

 cylindrical staminal tube, very slightly crenulate at its upper orifice 

 surmounted by eight or ten anthers. The elongated ovary is des- 

 titute of disk, and the trimerous, septicidal capsule opens from top to 

 bottom to allow the seeds, with posterior wing, to escape. Elutheria 

 consists of plants from the Columbian and Peruvian Andes, having 

 tetramerous flowers, imbricate or contorted petals, eight stamens in- 

 serted at the top of the tube in the interval of as many teeth, with 

 a connective prolonged in a long and slender strap, and an ovary with 

 four multiovulate cells. The capsular papyraceous septifragal fruit 

 contains seeds prolonged in a long wing, analogous to that of 

 Stvietenia. The leaves of Elutheria are alternate, imparipinnate, with 

 opposite folioles, dentate like a saw, tomentose ; the flowers are axillary. 



The species of Carapa form by themselves a small distinct group, 

 whose place in this series is uncertain. They have pluriovulate ovary 

 cells, bringing them near the preceding genera ; but the 4-5-merous 

 flowers are nearly those of Trichiliece, with an imbricate calyx. 



