CRUDE DRUGS. 43 1 



Inner Structure. — See Figs. i86; 284, A; 306. 



Constituents. — Strophanthin, a crystalline principle occur- 

 ring chiefly in the endosperm and varying from 0.95 to 3 per cent. ; 

 strophanthin is colored greenish with sulphuric acid, and yields on 

 decomposition a crystalline body called strophanthidin ; the other 

 constituents are kombic acid and about 30 per cent, of a fixed oil. 



Allied Plants. — The seeds of a number of other species and 

 varieties of Strophanthus find their way into the market, but 



Fig. i8s. A dehiscent follicle of strophanthus showing plumose seeds. 



these are usually more or less deficient in strophanthin and hence 

 do not give a greenish color with sulphuric acid. The most 

 important of these are the seeds of Strophanthus hispidus, a plant 

 growing in Upper Guinea and other parts of Western Africa. 

 These are smaller, thicker and less hairy than those of 5". Kombe 

 and yield less than i per cent, of strophanthin. The commercial 

 drug may contain other Strophanthus seeds, some of which con- 

 tain calcium oxalate prisms. 



