CRUDE DRUGS. 583 



acid is said to be prevented by sprinkling the hops with a small 

 quantity of alcohol before packing them. Hops lose their active 

 properties on keeping. 



Description. Cone-like, flattened, oblong or ovoid, 2 to 3 

 cm. long. 1.5 to 2 cm. wide, about 7 mm. thick, consisting of a 

 sharp-undulate rachis and about 50 membranous bracts, the lat- 

 ter distinctly veined, light green or brownish-green, glandular- 

 hairy, entire, 10 to 14 mm. long, 7 to 11 mm. broad, with acute 

 apex and rounded base, frequently infolded on one side and en- 

 closing a sub-globular, light-brown, very glandular akene ; the 

 seed with two flat, spirally coiled cotyledons and without a reserve 

 layer ; odor aromatic ; taste bitter. 



Constituents. Volatile oil about 0.7 per cent., of which 60 

 to 70 per cent, is humulene ; a crystalline, bitter principle, lupa- 

 maric acid; tannin 4 to 5 per cent.; resin 10 to 18 per cent.; 

 asparagin, about i per cent. ; trimethylamine ; choline or lupu- 

 line ; malic and citric acids, chiefly in the form of salts ; calcium 

 oxalate, and ash about 10 per cent. 



COLOCYNTHIS. BITTER APPLE. The fruit of Cit- 

 ritUiis Colocynthis (Fam. Cucurbitaceae), a perennial herbaceous 

 vine (p. 386), indigenous to warm, dry regions of Africa and 

 Asia, and cultivated in the northwestern provinces of India and 

 the countries bordering the Mediterranean. The fruit is col- 

 lected in autumn when ripe, and after removal of the epicarp by 

 paring, is quickly dried in the sun or by artificial means. The 

 commercial supplies are obtained from Turkey and Spain, the 

 finer grade coming from Turkey. The seeds should be removed 

 from the pulp before it is used. 



Description. Berry nearly globular, S to 7 cm. in diam- 

 eter (Fig. 254); light; externally yellowish-white; internally, 

 with three longitudinal, somewhat elliptical fissures 8 to 14 mm. 

 wide ; seeds numerous, ovoid, compressed, yellowish-green, and 

 borne on the divided parietal placentas betw'een the fissures ; odor 

 sHght; taste very bitter (Fi^. 93). 



Constituents. A bitter glucoside, colocynthin, 0.2 to 0.5 

 per cent., which may be crystallized but usually is obtained as an 

 amorphous powder that is inflammable, soluble in water and alco- 

 hol, and yields upon hydrolysis colocynthein ; a tasteless resin, 



