GENERAL PROPERTIES AND ACTIONS OF THE VENOM. 



93 



cipitation in the different tubes eventually becomes the same in all cases. 

 Whether the precipitins owe their origin to and react with the venom proper or 

 proteid material admixed to the venom, can not be decided without a deter- 

 mination of the chemical character of the venom.** 



The serum of the immunized rabbits contains also a precipitin which re- 

 acts with the blood of the Heloderma. This reaction was, however, quite weak 

 and only a small amount of precipitate was found in serum-blood mixtures. 

 Whether this reaction is due to the same precipitin which reacts with the 

 venom or to a specific precipitin for the heloderma blood is doubtful. There 

 is a strong possibility that it is a specific heloderma-blood precipitin, since, 

 as we have stated earlier, the venom frequently contained small quantities of 

 blood which were dried and again dissolved simultaneously with the venom. 



DOES BLOOD SERUM OF HELODERMA CONTAIN A VENOM ANTITOXIN ? 



The antitoxic properties of the serum of both normal helodermas and the 

 helodermas from which the venom gland had been removed were tested. Be- 

 fore injection, the serum was allowed to stand mixed with the venom for periods 

 of from 30 minutes to an hour at room temperature. These mixtures were 

 then injected into mice and at the same time control mice were injected with 

 the same quantities of venom which had not been mixed with serum. 



* Poison glands had been removed 66 days previously (serum 1). 

 t Poison glands had been removed 30 days previously (serum 2). 

 j Poison glands had been removed 7 days previously (serum 3). 

 Injected at same time as mice injected with serum 3. 

 If Injected at same time as mice injected with serum 1. 

 "The results obtained by Dr. Alsberg make it almost certain that the precipitins formed owe their origin not 

 to the injection of the venom proper but to admixed proteid material. 



