82 



THE VENOM OF HELODERMA. 



In making the suspensions, the various organs were first minced and 

 crushed and then added to a very small quantity of 0.85 per cent sodium- 

 chloride solution. This mixture was allowed to stand for about 2 hours before 

 being injected into the animals. In all cases the effects of the organ extracts 

 were tested on mice. 



We found that the injection of 1 c.c. of the suspension of kidney, pancreas, 

 and spleen of Heloderma had no visible effect upon the animals. Two mice in- 

 jected with liver suspension, one with 1 c.c. the other ivith 0.5 c.c, died on the 

 third day after the injection, in all probability not as a result of the injection, 

 but due to starvation. Two other animals injected with 1 c.c. and 2 c.c. of 

 liver suspension, respectively (not at the same time as the other two), showed 

 no ill effects. Three animals were injected with heloderma egg which had been 

 mixed with an equal quantitj^ of sodium-chloride solution; they received either 

 0.5 c.c, 1 c.c, or 2 c.c. of this mixture and none of them was affected by the 

 injection. Several animals which received variable doses up to 1 c.c. of the 

 suspension of the supposed lachrymal gland or in which pieces of this organ 

 were placed in a subcutaneous pocket remained perfectly well. From the above 

 experiments it would appear that none of the organs of the Heloderma, includ- 

 ing the gland which is found in the eye-socket, have a toxic action. 



Two mice were injected with urine of the Heloderma; one received 1 c.c, 

 the other 2 c.c Neither of these animals showed any disturbances following 

 the injection. 



Two mice were injected with serum of the Heloderma. Both received 2 

 c.c. of serum, but no toxic effect was evident. 



One mouse injected with 0.25 c.c. of heloderma bile died after 2 hours, 

 while another mouse which received 0.1 c.c. of bile survived the injection. In 

 order to test the toxicity of bile, we injected a mouse with 0.5 c.c. of dog's bile 

 and this animal died in 2 hours. It is evident that the toxic effect of the helo- 

 derma's bile is due not to any content of venom, but to some substance con- 

 tained in bile, such as the bile-salts. In order to further show that the toxic 

 effect of the heloderma's bile was not due to venom, we injected some mice 

 with various quantities of bile and venom and other mice with like quantities of 

 venom alone. The mice which received the injections of bile and venom did 

 not die sooner than those which received the venom alone. On the other hand, 

 the addition of bile to the injected venom did not diminish the toxicity of the 

 venom, since the mice which received like quantities of venom died approxi- 

 mately the same length of time after the injection, irrespective of whether bile 

 had or had not been added. 



These results obtained with the organs and also with the eggs of Heloderma 

 differ markedly from those obtained with the blood of snakes and certain other 

 animals possessing venom-secreting glands. The blood of the latter has by 

 various investigators* been found to be very poisonous; while the blood of 

 Heloderma is innocuous. It is possible that the toxicity of certain organs of the 



•Phisalix et Bertrnnd, Arcliiv. de Physiol. 1894; Calmctte, Compt. Rend, de la Soc. Biol., 1S!M. x. ser. i; 

 Wehrmann, Annalos do I'lnstitut. Pasteur, xi, 810, 1897. 



