HEMOLYTIC PROPERTIES OF HELODERMA VENOM. 



167 



We tested venom which had been heated to 100 C. for 10 minutes and 30 

 minutes, and to 120 C. for 15 minutes. Venom which had been heated to 

 100 C. for 10 minutes was quite as active as unheated venom; when heated to 

 100 C. for 30 minutes the venom lost most, if not all, of its power to hemolyze 

 the various corpuscles (some variations were observed in individual cases, de- 

 pending probably upon the susceptibility of the individual corpuscles). When 

 venom was heated to 120 C. all hemolytic power was lost. It should be noted 

 that unheated venom always produced more rapid hemolysis than did the 

 venom which had been heated to 100 C. for 10 minutes. 



1 c.c. of 5 per cent suspension of turtle corpuscles and 0.1 mg. of lecithin. 



The results were in general the same with turtle, heloderma, and guinea- 

 pig corpuscles. 



We also compared the influence of heat on the venoms of the Heloderma 

 horridum and Heloderma suspectum, finding an approximately similar behavior, 

 although the venom of the Heloderma horridum was slightly more affected by 

 the heating than the venom of the Heloderma suspectum; the two venoms pro- 

 duced the same degree of hemolysis when heated for 10 minutes to 100 C, but 

 after being heated to 100 C. for 30 minutes the venom of Heloderma horridum 

 was weaker than that of suspectum. 



1 c.c. of 5 per cent suspension of rabbit corpuscles and 0.05 mg. of lecithin. 



The action of heat upon the two venoms is therefore in the main the same. 

 The venom of the Heloderma is distinctly heat resistant, approximately equally 

 if not more resistant than the hemolysins of certain snake venoms. The hemo- 

 lytic property of the venom of Heloderma is, however, not quite as resistant 

 as the neurotoxic property. 



