Adsorption of Venom of Heloderma suspectum. 93 



least adsorptive power of the organs examined ; especially the 

 brain of Heloderma has hardly any adsorbing power. On the 

 other hand some other organs of Heloderma, namely, liver and 

 kidney, have more adsorbing power than the organs of any other 

 animal. Next in the order of adsorbing power come the organs 

 of the turtle and these are followed by the liver and kidney of the 

 pigeon, frog and guinea-pig, while dog and rabbit organs have 

 least adsorbing power. 



Certain differences seem to exist in the firmness with which the 

 adsorbed venom is fixed to various organs. The kidney of Helo- 

 derma seems to hold the venom more firmly than the liver of the 

 same animal. Of the greatest interest, however, appears to us the 

 fact that the organs of Heloderma adsorb a larger quantity of their 

 own venom than the organs of any other animal which we exam- 

 ined. While the blood of the Heloderma does not contain any 

 antitoxin and, as Dr. E. P. Corson White has shown in our lab- 

 oratory, no complement fixation takes place on mixing venom and 

 blood serum of Heloderma, the liver and kidney of Heloderma 

 show a definite specific relation to the venom of Heloderma, pos- 

 sessing a relatively great power of binding it. With some degree 

 of justification it may be suggested that this specific relation is one 

 of the factors concerned in the natural immunity of Heloderma 

 against its own venom, such a union preventing the venom from 

 a combination with certain parts of the nervous system. Further- 

 more, inasmuch as the adsorbing power of the brain is very slight, 

 while on the other hand venom exerts its lethal action through its 

 influence upon certain parts of the brain, we may assume that very 

 small quantities of the venom when combined with brain substance 

 are sufficient to kill the animal. 



We wish to direct attention to the possibility that organs of 

 those animals that are more closely related to Heloderma, as, for 

 instance, the turtle, adsorbed more venom than more distinctly 

 related animals, as the dog and rabbit. This, however, is merely 

 brought forward as a suggestion and it must be left to further 

 work to confirm or invalidate it. 



