76 



THE VENOM OF HELODERMA. 



In none of the rabbits were any especial changes found at the autopsy. In 

 one animal, however, which died 18 hours after receiving three capsules, each 

 containing 0.2 c.c. of venom, small hemorrhages and a few ulcers were noted in 

 the gastric mucosa. The capsules were always found to be surrounded by a 

 thick fibrinous exudate, which appeared to be partly organized in the cases in 

 which the animals survived. 



In two cases we made hemoglobin, red blood-cell, and leucocyte counts 

 before and several days after the giving of the capsules. The results of these 

 are given below: 



These experiments are too few in number and the results are too irregular 

 to allow of any definite conclusions. It appears, however, that this method of 

 administering venom has not a very marked effect on the elements of the 

 blood. 



.\DMINISTERING FRACTIONAL DOSES OF VENOM. 



In pigeons and mice small sublethal doses of venom were repeatedly in- 

 jected in order to determine the rapidity with which the venom was destroyed 

 by or eliminated from the body. For this purpose we used six pigeons. The 

 following table shows the amounts injected, the time which elapsed between 

 the injections, and the ultimate result: 



Influence of injection of fractional doses of venom into pigeons. 



From these experiments we learn that when the dose of venom usually 

 lethal for pigeons (0.8 mg.) is injected in fractional parts, with an interval of 3 

 hours between the injections, the animal survives the injection. If slightly 

 more than the minimal lethal do.se be injected, with a similar interval of time 

 between the two injections, the pigeons still may survive. If, however, within 

 a period of 3 hours, as much as 12 mg. of venom be injected, thus half again as 

 much as the minimal dose, the pigeons die. When the interval between the 

 two injections of venom is shortened to an hour the animal dies more quickly 

 than when a longer time elapses between the two injections. It therefore 



