GENERAL PROPERTIES AND ACTIONS OF THE VENOM. 59 



toxic substances was not complete. The results obtained by injecting into 

 animals, at different intervals, material from inside and outside the dialyzer 

 were as follows: At the end of 1 day the solution outside the dialyzer had 

 acquired scarcely any of the toxic substance and the solution inside showed 

 scarcely any decrease in toxicity ; at the end of 2 days the symptoms produced 

 by material from outside the dialyzer were marked but not grave, while death 

 followed the injection of a similar quantity of the solution inside the dialyzer; 

 at the end of 3 days the symptoms produced by the injection of fluid from out- 

 side the dialyzer were grave, but less serious than those produced by material 

 from inside the dialyzer; at the end of 4 days the symptoms produced by 

 material from outside the dialyzer were grave and with large doses sometimes 

 fatal, but they were still less severe than the symptoms produced by similar 

 quantities of the material within the dialyzer. Throughout there was noted a 

 gradual decrease of the toxicity of the solution inside the dialyzer. Where 

 large quantities of the solution were injected, control animals were injected 

 with equal volumes of sterile salt solution. All the solutions were sterilized 

 before injecting. In these experiments mice and rats were used to test the 

 toxicity of the solutions. In this respect the heloderma venom behaves in a 

 manner similar to the venom of the Colubridae, which passes slowly through 

 vegetable membranes. The gradual decrease in toxicity of the solution within 

 the dialyzer and the corresponding increase in toxicity of the solution outside 

 the dialyzer is apparent in the following protocols: 



Veno7}i Dinlyzing 24 hours. 

 Outside Dialyzer. 

 Rat 104, 100 g. 

 June 25, 4 o'clock injected subcutaneously 1 c.c. of solution. 4^ 4S'° slightly- 

 affected. June 26 recovered. 

 Mouse 26. 

 June 25, 4^ 02°> injected subcutaneously 0.2 c.c. of solution. 4^ 45"° respiration 

 rapid; otherwise well. June 26 recovered. 

 Inside Dialyzer. 

 Rat 105, 110 g. 

 June 25, 4^ 15°' Injected subcutaneously 1 c.c. of solution. .'if' 45" very gravely 

 affected. 4^ 65°' dead. 

 Mouse 27. 

 June 25, 4^ K'^ injected subcutaneously 0.2 c.c. of solution. 4^ 45"" lying down; 

 breathing forced. 5 o'clock dead. 

 Venom Dialyzing 44 hours. 

 Outside Dialyzer. 

 Rat 24, 100 g. 



June 5, 12*' 75" injected intraperitoneally 4 c.c. of solution; appeared somewhat 

 drowsy all day, but recovered. 

 Rat 26, 100 g. 



June 5, 12^ i7" injected intraperitoneally 2 c.c. of solution; drowsy; recovered. 

 Rat 28, 120 g. 



June 5, 12^ IS"" injected intraperitoneally 1 c.c. of solution; slightly drowsy; 

 recovered. 

 Inside Dialyzer. 

 Rat 25, 100 g. 



June 5, 12^ 20'° injected intraperitoneally 4 c.c. of solution. 13^ SO" lying 

 down; very much affected. 7^'' 40"° dead. 

 Rat 27, 100 g. 



June 5, 12'' 22" injected intraperitoneally 2 c.c. of solution. 12^ 40" breath- 

 ing diiBcuIt, lies on side. 12^ 45" breathing very difficult, legs paralyzed. 

 ^gh j^yw. reflexes absent. 1 o'clock dead. 

 Rat 29, 120 g. 

 June 5, W' 25" injected intraperitoneally 1 c.c. of solution. 12^ 45" lies on 

 side. i o'c^ocfc dying. i"" SO" dead. 



