24 ON THE NATURE AND ACTION OF THE 



In a previous communication we have described the effect of 

 the poison of Naja tripudians upon warm-blooded animals, and 

 have illustrated it by experiments on the dog, raljbit, guinea- 

 pig, and fowl. 



We purpose in the present paper to compare its action with 

 that of the poison of the Dahoia Russdlii, a viperine snake, to 

 describe its effects upon cold-blooded animals and invertebrata, 

 and to examine in detail its action upon the various organs of 

 the body. 



In our former paper we stated that the general symptoms of 

 poisoning by cobra-venom are depression, faintness, hurried 

 respiration and exhaustion, lethargy, unconsciousness, nausea, 

 and vomiting. In dogs, guinea-pigs, and rabbits, peculiar 

 twitching movements occur, which seem to represent vomiting 

 in them ; occasionally, in fact, dogs and guinea-pigs (Experi- 

 ment XX) do vomit, and dogs are profusely salivated. As the 

 poisoning proceeds, paralysis appears, sometimes affecting the 

 hind legs first and seeming to creep up the body, and sometimes 

 affecting the whole animal nearly at the same sime. There is 

 loss of co-ordinating power of the muscles of locomotion. 



Haemorrhage, relaxation of the sphincters, and involuntary 

 evacuations, not unfrequently of a sanguineous or muco- 

 sanguineous character, often precede death, and are generally 

 accompanied by convulsions. 



In fowls, the appearance is one of extreme drowsiness : the 

 head falls forward, rests on the beak, and gradually the bird, 

 no longer able to support itself, crouches, then rolls over on its 

 side. There are frequent startiugs, as if of sudden awaking from 

 the drowsy state. 



The following experiments upon pigeons and guinea-pigs show 

 that the general symptoms produced by the poison of the 

 Dahoia are nearly the same as by that of the Naja. The local 

 symptoms are greater extravasation of blood and effusion into 

 areolar tissue. In Experiment III it was noted that greater 

 lethargy and less violent convulsions occurred in the pigeon 

 poisoned by cobra-venom than in that poisoned by Dahoia ; but 

 this might readily be due to individual difference in the bird ; 

 and an opposite result is noted in Experiment YII upon a 



