34 Papilionaceas, Rosaceae [ch. 



M. Audibert (near Beaucaire) reported the death of 80 sheep from eating 

 the press-cake, which is stated to have more pronounced properties 

 than the oil. It has been found as an impurity in linseed cake and maize 

 meal. {Jour. Roy. Agric. Soc, 1892.) 



Toxic Principle. The toxic properties of the bean are due to Ricin, 

 a toxin which is similar to bacterial toxins, and the activity of which is 

 destroyed by heating to 100° C. The beans also contain the alkaloid 

 Ricinine (CgHgOaNg) , the toxic properties of which are regarded as doubt- 

 ful. (See Deane and Finnemore, Yearbook of Pharmacy, 1905, p. 473.) 



Symptoms. These usually appear some days after the ingestion of 

 the beans or press-cake. There is generally purging. Broad observed 

 in an affected horse loss of appetite, shivering, cold extremities, dejec- 

 tion, abdominal pain, constipation, temperature 103° F., pulse 70, and 

 death in about three days. 



REFERENCES. 

 4, 16, 66, 73, 128, 205. 



ROSACEiS;. 



Cherry Laurel {Prunus laurocerasus L.). This exceedingly com- 

 mon ornamental shrub has caused the poisoning of numerous cattle and 

 sheep on the Continent, but is apparently less harmful in Great Britain 

 — and in any case animals are not much given to eating the foliage of 

 this shrub, the strong smell of the leaves when bruised affording a warn- 

 ing of its unwholesome character. Gerlach recorded the intoxication 

 of 25 sheep. Bibbey also records the poisoning of 15 sheep by 

 laurel, some of them dying {Farmer and Stockbreeder, Jan. 29, 1912). 

 On the other hand, Henslow wrote of his cows that they "completely 

 ruined a long laurel hedge adjoining the field in which they lived; 

 but this abnormal food did no harm either to themselves or the milk 

 they produced." 



Toxic Principle. So long ago as 1803 Schrader showed that the 

 cherry laurel contains a substance yielding prussic acid. The leaves 

 contain the cyanogenetic glucoside Prulaurasin {Q^^-^^0^), and an 

 enzyme-emulsin which, by its action on the cyanogenetic glucoside, 

 induces the formation of prussic acid, which is the actual cause of 

 poisoning. The percentage of the glucoside appears to be greatest 

 about July and August. By a microchemical examination Peche has 

 clearly localised hydrocyanic acid compounds in the leaf parenchyma. 



Symptoms. In poisoning by Cherry Laurel there is bloating, 

 inability to rise, loss of sensation, difficult breathing, convulsions and 



