148 REPORTS ON THE STATE OF SCIENCE^ 



cultivate it for use as forage, and as a result occasional poisoning cases 

 among cattle have occurred in almost all the countries in which this 

 practice has been adijpted. The toxicity of sorghum seems to be enhanced 

 in seasons of drought. In Egypt the young plant has long been known 

 to be poisonous, and there it appears never to be applied as a green fodder 

 by the natives. 



Dhurrin has the formula C,4H,,0,,N, and on hydrolysis with hot 

 dilute hydrochloric acid or by emulsin, which occurs in the plant, yields 

 one molecule each of prussic acid, para -hydro xybenzaldehyde, and dextrose. 



When decomposed by heating with alkalis it yields ammonia and 

 dhurrinic acid. 



C,JT„0,N + 2H,0 = NII3 + C,,TI,„0,. 

 Dhurrin. Ammonia. Dliurriiiic 



acid. 



And the latter, on further hydrolysis by hot dilute acids, decomposes into 

 a molecule each of jj. -hydroxy mandelic acid and dextrose. 



C,,H„0„ + H.,0 = C.H.G, + CJI,A 

 l)hurrinic acid. j;.-Hydrox}man- Dextrose. 



delic acid. 



These reactions are explained by regarding dhurrin as the dextrose 

 ether of parahydroxybenzaidehydecyanohydrin, thus : — 



ch/ \c — ch<; 



I I \CN 



HO.C . /CH 



u.-Hydroxybenzaldeliydecyauo- Dextroac 

 hydrin residue. residue. 



it is probably, therefore, a ;?ara-hydroxy derivative of mandelic 

 hitrile glucoside or of one of its isomerides. 



Lolusin. 



It will be observed that all the cyanogenetic glucosides so far de.scribed 

 are of a type in which the cyanogen radicle is attached to the non-sugar 

 portion of the nucleus, forming with it a cyanohydrin. It is, however, 

 obvious that another type may exist, in which the cyanogen radicle is 

 associated with the sugar residue to form a sugar cyanohydrin. The only 

 substance of this second type yet known was obtained ^ from the stems 

 and leaves of an Egyptian plant, Lotnn ambicus, growing along the valley 

 of the Nile, where it is known as 'khuther.' The Arabs have long 

 known that it is poisoiaous in the early stages of its growth, and that it 

 becomes a useful forage when allowed to mature. The plant was a great 

 source of trouble to the Anglo-Egyptian army during the first Sudanese 

 war, since many of the transport animals were poisoned by eating it. 

 This led eventually to its investigation at the Imperial Institute, and it 



> Ducstan and Henrj-, Phil. Trans., 1901, B, 194, 513. 



