398 SCIENTIFIC AND APPLIED PHARMACOGNOSY 



glands between the sinuses; fruit a light yellowish-brown, 3-locular 

 capsule, about 1 mm. in length and containing very minute, ovoid- 

 tetragonal seeds, which are distinctly wrinkled when mature; inodor- 

 ous; taste slightly bitter. 



Constituents. An alkaloid, 0.1 per cent; a glucosidal sub- 

 stance, 0.4 per cent; several resins; caoutchouc; tannic acid; 

 mucilage; sugar; protein; ash 8 to 12 per cent. 



Allied Plants. A number of species of Euphorbia growing in 

 eastern and central North America are used in medicine. The roots 

 of Euphorbia corollata were at one time used as an emetic. (Consult 

 Holm, Merck's Report, 1910, p. 126.) 



SEMEN RICINI. Castor-oil Seeds or Castor Bean. The ripe 

 seeds of Ricinus communis (Fam. EuphorbiacesB), an annual herb 

 in temperate regions, but a shrub-like perennial in tropical and 

 sub-tropical countries. The plant is indigenous to southern Asia 

 and tropical Africa, and is extensively cultivated. There are a very- 

 great many varieties and the seeds vary in size and color. The larger 

 seeds are imported from India, the smaller seeds coming from France 

 and Italy. 



Description. Anatropous, elliptical-ovoid, somewhat compressed, 

 from 8 to 18 mm. in length, 4 to 12 mm. in breadth and from 4 to 7.5 

 mm. in thickness; externally grayish-brown, mottled, varying 

 considerably in color, smooth and tortoise shell-like, with a prom- 

 inent whitish caruncle at the somewhat pointed end, and from 

 which there arises the narrow and somewhat raised raphe which ex- 

 tends, on the flat side or ventral surface, to the chalazal end of the 

 seed; seed-coat thin, brittle, consisting of an outer grayish-brown 

 testa and a thin whitish tegmen; endosperm large, white, oily and 

 divided into two nearly equal portions usually having a lenticular 

 cavity between them, and on either side of which is a thin foliaceous 

 cotyledon, slightly detachable from the endosperm, and connected 

 with the short caulicle and radicle, the latter directed towards the 

 micropyle. 



Inner Structure. An epidermal layer of thin-walled tabular cells, 

 the inner being somewhat porous and the outer somewhat thickened 

 and variously colored ; a broad band consisting of from 4 to 10 rows 

 of large thin-walled, more or less collapsed cells usually referred to as 

 star parenchyma, and from which layer the caruncle is developed; 

 beneath this is a layer of radially elongated, thin-walled, colorless 

 cells, having small triangular intercellular spaces; a fourth layer, 

 made up of a single row of palisade-like stone cells, attaining a length 

 of 2 mm., having very thick, porous, yellowish-brown walls, and con- 



