28 PapilionacesB [OH. 
14 recovered. In the famous Bristol Tramways case (1894) 123 out of 
800 horses became ill owing to being fed on the peas of L. sativus, and 
many died. There are few records of harm to cattle, sheep and pigs, 
and Watt quotes Don to the effect that pigeons lose their power of 
flight by feeding on the peas. Very large quantities of the peas are used 
for feeding purposes, and the fact that the losses are not larger is 
probably because the peas only comprise a small proportion of the 
ration or are cooked before use. 
After boiling or roasting the peas appear to be less harmful, as they 
are eaten in India when cooked, or ground into flour and converted into 
bread though Cornevin states that drying and cooking does not 
destroy the toxicity, while boiling for some time showed that at any 
rate part of the toxic substance passed into the water, which became 
toxic and caused death, the boiled seeds losing the greater part of their 
poisonous property and not causing accidents when the water was 
rejected. MacDougall states that as far as experimental evidence was 
available (1894) it seemed to show that boiling the seeds before use 
renders them innocuous. 
Lathryism usually only supervenes when the use of the peas for food 
is prolonged, and the peas are taken in considerable quantity, but 
it is possible that there is wide variation in the toxicity of different 
samples, owing to differences in soil, climate, and other factors. In man, 
Lathryism is stated to be common in Spain, Italy, Russia and India, 
owing to continued use of bread from flour of the three species of Lathyrus 
mentioned above. It is said especially to affect males. 
Toxic Principle. Nothing certain as to the poisonous properties is 
known, attempts to isolate the toxic substance having failed (Kobert), 
though Smith gives it as prussic acid, apparently indicating a cyano- 
genetic glucoside. This, however, can hardly be so, as the poison is 
cumulative, and may not show its effects for weeks or months, or, in 
man, even years according to the quantity of peas eaten. 
Symptoms. Lathyrism is only produced when the ration consists 
largely of the pea for a considerable period (see above) ; in the horse 
fed exclusively on the pea, the tenth day ; but when one or two quarts 
are given daily, only towards about the 80th day. Moreover, the malady 
may declare itself as long as fifty days after the cessation of the pea 
feeding (Lander). 
In general Lathyrism is marked by paralysis of the lower extremities 
in man and the hind limbs in, animals, owing to the degeneration of the 
muscle fibres, and possibly to affection of the nerves. In horses there 
