220 THE VENOM OF HELODERMA. 



lethal doses lived only a little longer than the control, it would appear that 

 some factor other than the adsorption of the venom was the cause for the sur- 

 vival of this animal. In another experiment one animal, injected with 3| 

 lethal doses, survived. The residue of the turtle-brain venom mixture in- 

 jected into mice caused death in one case, while the only other mouse injected 

 survived. In the case of turtle brain we have to make the same reservation 

 as in the case of heloderma brain, namely, that a considerable part of the 

 venom may have been, and in all probability had been, adsorbed by the small 

 particles suspended in the supernatant fluid. A small part had fixed itself 

 upon the surface of the larger particles of the suspension. 



Only two mice were injected Avith the supernatant fluid from the fresh- 

 venom turtle-liver mixture and both of these died. 



In experiments in which dissolved dry venom was used, turtle liver seemed 

 to adsorb the venom better than turtle brain; 5 of 27 mice injected with the 

 supernatant fluid survived. These five animals had for the most part been 

 injected with quantities corresponding to 83 lethal doses of venom, in one case 

 with a quantity equivalent to 65 lethal doses. Turtle liver may, therefore, 

 adsorb as much as 85 per cent of the venom, and usually adsorbs more than 

 70 per cent. Three out of four injected with the residue of this turtle-liver 

 venom mixture survived the injection. Whether venom was held very firmly 

 or destroyed by the liver pulp or whether the venom was washed off by the salt 

 solution we can not state, although it is improbable that the latter explanation 

 is correct. 



Two mice were injected with quantities of the supernatant fluid from the 

 turtle-kidney fresh-venom mixture, equivalent to one and two lethal doses of 

 venom respectively, and both of these animals survived; 8 of the 28 mice 

 injected with the supernatant fluid from the mixture with dry venom survived, 

 and 2 of the 8 had been injected with quantities corresponding to 6| lethal 

 doses. The injection of the residue of turtle-kidney venom mixture was lethal 

 in three out of four cases. Turtle kidney adsorbs approximately the same 

 amount of venom as turtle liver. 



Two mice were injected with the supernatant fluid from a mixture of 

 venom solution and turtle egg; one of these, receiving 85 lethal doses, died as 

 soon as the control mouse, while the other, injected with a quantity correspond- 

 ing to 65 lethal doses, lived longer than the control. One mouse injected with 

 venom mixed with turtle serum died as soon as its control. Neither the admix- 

 ture of turtle egg or turtle serum diminishes the toxicity of the venom to any 

 marked degree. 



Of 10 mice injected with the supernatant fluid from a frog-liver venom 

 mixture, 6 died as soon as their respective controls, 3 lived longer, and 1 sur- 

 vived the injection. The only mouse which survived had been injected with a 

 quantity of fluid corresponding to 6f lethal doses. Hence it would seem that 

 the adsorptive power of frog liver is very slight. 



Of 3 mice injected with frog-liver venom residue, 1 died and 2 survived. 

 These results agree with the findings in the experiments in M'hich the super- 

 natant fluid was injected. 



