108 FRUITS 



Much of the colocynth at present imported consists of the pulp free 

 from the seeds ; for the latter some use, possibly the production of 

 fixed oil, has apparently been found. 



Constituents. The chief constituents of colocynth pulp appear to 

 be an alkaloid producing very drastic purgation even in small doses, 

 and amorphous resins soluble in ether and chloroform which also are 

 powerful purgatives. Other constituents are a crystalline alcohol, 

 citrullol, and a- elat erin ; neither of these are purgative; a-elaterin 

 is also present in elaterium (see ' Elaterium '). The presence of a 

 crystallin glucoside, colocynthin, formerly reported, has not been 

 confirmed. The pulp also contains from 1-0 to 1-3 per cent, of fixed 

 oil and yields from 7 to 13 per cent, of ash ; it contains no starch. 



The small amount of fixed oil and the large amount of ash have 

 been utilised to distinguish the powdered fruit from the powdered 

 pulp. The seeds contain from 15 to 17 per cent, of oil, and yield 

 only 2-5 to 3'Oper cent, of ash. Powdered fruits yield from 4 to 6 per 

 cent, of ash and about 10 per cent, fixed oil. Microscopical examina- 

 tion of the powder yields more definite results. Colocynth pulp consists 

 of very large thin-walled parenchymatous cells with occasional fibro- 

 vascular bundles, accompanied by tubular cells but no sclerenchy- 

 matous cells are present in it, whereas the seed-coats abound in 

 sclerenchymatous tissue which can be readily detected and identified. 



Varieties. Turkey colocynth, which is the most esteemed, is imported 

 from Syria, Cyprus, &c. ; the fruits are carefully peeled, nearly white, 

 and contain a larger proportion of pulp. During and since the war 

 large quantities of very similar Sudan colocynth have been imported. 



Spanish colocynth is less sightly, often discoloured, and contains 

 less pulp. 



Persian colocynth occurs in small, shrunken balls with little pulp ; 

 it is now seldom imported. 



Mogadore colocynth is occasionally imported ; it is unpeeled. 



j. Colocynth is a gastro-intestinal stimulant or irritant and 

 one of the most powerful of the official purgatives, acting as a hydra- 

 gogue cathartic. It is employed as an occasional purgative to produce 

 free evacuation of the bowels in bilious derangements or chronic 

 constipation, but as it causes griping is seldom prescribed alone. 



CARAWAY FRUITS 



(Fructus Carui) 



Source, &C. Caraways are the ripe fruits of Carum Carvi, Linne 

 (N.O. Umbelliferce) , an erect biennial herb distributed over central 

 and northern Europe. The plant is found in Britain, apparently 



