POISONOUS PLANTS 143 



The doses refer to ingestion of autumn and winter leaves, 

 and show, as is usual, a relatively great degree of resist- 

 ance on the part of the ruminants. 



There are several recorded instances of yew poisoning in 

 man, generally of lunatics, from which it appears that the 

 poisonous dose of leaves for the human subject is small. 

 In these cases, quoted by Taylor ' On Poisons,' it is note- 

 worthy that the narcotic effects predominate, and it is also 

 observable that, as with animals, a comparatively short 

 period of time elapses between dosage, and the onset of 

 symptoms and death. 



Symptoms. — A remarkable feature of yew poisoning is , 

 its rapidity.^' ^ Often the effects only appear in cattle when 

 chewing the cud. Whilst quietly chewing, they drop as if 

 shot (Wallis Hoare).* In some examples recorded in the 

 literature the animal died whilst in the act of eating the 

 plant, ^ or was found to have fallen and died suddenly and 

 without evidence of a struggle. The animal will stop sud- 

 denly whilst working, start blowing and trembling, stagger, 

 fall on haunches, then on side, and die quietly. Death 

 occurs in about five minutes, with symptoms like apoplexy.'-^ 

 A case of death after sixteen to seventeen hours of a 

 colt is recorded by '' Jarvis,^ who points out that the 

 plant was taken on a full stomach, but that paralysis 

 of the alimentary system, with stoppage of digestion, 

 immediately ensued. 



Post-Mortem Appearances. — The stomach is generally 

 distended with gas, owing to fermentation following the 

 arrest of digestion. Intense inflammation is almost in- 

 variably observed, but does not appear to be a salient 

 feature in the cases amongst the human subject quoted by 

 Taylor. The stomach is found to contain dark green 

 ingesta,^ and sprigs, berries, or leaves of yew may be easily 

 recognised, but if dry sprigs were eaten they may not be 

 recognised. The inflammation rarely extends to the intes- 

 tines,^°' "■ ^^ which also rarely contain fragments of yew. 

 The liver, spleen, and lungs are engorged with dark blood. 

 The right heart is empty, and the left heart contains more 



