THE ACTION OF SNAKE YENOM UPON COLD-BLOODED 



ANIMALS. 



By HIDEYO NOGUCHI, M. D., 

 Assistant in Pathology, University of Pennsylvania. 



Since the writings of Fontana, Weir Mitchell alone seems to have concerned him- 

 self with the study of the action of snake venom upon cold-blooded animals. Having 

 studied and described the action of rattlesnake venom upon frogs and upon Crotalus 

 itself, it was his intention, as will appear from a paragraph in his earlier paper on 

 venom, to extend his observations to a wider class of animals. Thus he writes : 



" It was my intention to examine, in the next place, the effects of the venom 

 upon leeches, fish, eels, and crustacean animals, but for some reasons, which it is 

 needless to relate, I was obliged to postpone these observations until some future 

 occasion."* 



The present investigation is the outcome of Dr. Mitchell's interest in this subject, 

 and has been rendered easily possible by the facilities of the Marine Biological 

 Laboratory at Woods Hole, Massachusetts, and by the aid of a grant from the 

 Carnegie Institution of Washington. I wish to thank Dr. Mitchell for arousing my 

 interest in this subject and for many suggestions as to the manner of its pursuit. I 

 am also under obligations to Prof. C. O. Whitman for placing at my disposal the* 

 materials for carrying on the study. 



The following orders of animals were tested against venom : Reptilia, Amphibia, 

 Pisces, Insecta, Crustacea, Vermes, Mollusca, Echinodermata. 



Several kinds of venom were employed : cobra, water moccasin, and rattlesnake. 

 All had been previously dried, and hence they were dissolved, before injection, in 

 sterile sea water or normal saline solution, according as they were to be introduced 

 into fresh or salt water animals. The mode of injection varied with the animal 

 species employed : in higher forms the peritoneum was selected, in lower forms the 

 body cavities or water vascular system. Some of the vermes gave unsatisfactory 

 results in respect to the dosage because of the strong muscular contraction produced 

 by the needle puncture and the presence of septa throughout the body. It was almost 

 impossible to calculate the exact amount of venom introduced into these animals. 



Each experiment was accompanied by at least two control animals maintained 

 under precisely the same external conditions. In every case in which the cause of 



* Researches upon the Venom of Rattlesnake, with an Investigation on the Anatomy and 

 Physiology of the Organs concerned. Smithsonian Miscellaneous Collections, volume XII, 

 Washington, 1861. 



