22 THE VENOMS OF CERTAIN THANATOPHIDE^E. 



being much swollen, the leg stiff, the muscles at the point of injection are paralyzed, and 

 sensibility of the leg destroyed. The pigeon lies on its side unable to stand, is exceedingly 

 prostrated, and breathes laboriously. Observation now ceased until 8 A. M. following morn- 

 ing, when the animal was found dead and in general rigor mortis, excepting the muscles at 

 point of injection. 



Autopsy. The tissues were dark, congested, and suffused with serum for an area of one 

 and a half inches from point of injection. The viscera of the thoracic and abdominal cavities 

 appeared slightly congested ; the heart was arrested in systole and contained dark clots ; the 

 blood everywhere was dark and clotted. Microscopically the muscular fibres did not appear 

 to be greatly disorganized, although in some of the fibres no transverse strias or nuclei could 

 be discovered. 



TJie Effects of Dry Heat. Experiment. 0.03 gram of dried (Crotalus adam- 

 anteus) venom was subjected in a dry oven to a gradually rising temperature to 

 83. 5 C C., and maintained at this point for half an hour. The venom, after cooling, 

 was dissolved in 1 c. c. of distilled water. 



2:57. Injected the above into the thigh of a pigeon. 



4:49. Violent convulsions and death. Local effects decidedly marked. 



Experiment. Repeated the above, but subjecting the venom to a temperature 

 of 100 C. for ten minutes. 



3:42. Injected into the thigh of a pigeon. 



6:00. No decided symptoms. On the following morning the animal was dead. The local 

 effects were marked. 



Experiment. Repeated the above, but subjecting the venom to a temperature 

 of 110 C. for thirty minutes. 



4:46. Injected into the thigh of a pigeon. 



5:25. Convulsions. 



5:45. Died. The local effects were marked. 



From these results it seems clear that heating the dry venom to a degree above 

 boiling point does not apparently alter its poisonous activity. The delay in 

 the occurrence of death in the second experiment suggests that the venom was 

 altered, but in the third experiment in which the temperature was even higher, 

 and this degree of heat maintained for a much longer time, death occurred even 

 sooner than in the first experiment, showing that the differences must have been 

 dependent upon conditions in the animals. 



The Effects of Moist Heat. Experiment. 0.03 gram dried venom (Crotalns 

 adamantens) was dissolved in 1 c. c. distilled water, and gradually heated until a 

 flocculent precipitate occurred. 



This was injected into the thigh of a pigeon in the evening. The next morning the animal 

 was found dead. 



Experiment. 0.03 gram dried venom (Crotalus adamanteiis) was dissolved in 

 1 c. c. distilled water and subjected to a gradually rising temperature to 50 C. 



3:49. Injected the above into the breast muscles of a pigeon. 



3:51. Very weak, pupils apparently contracted, trembling; breathing laborious. 



4:00. Dead. At the point of injection the tissues were decidedly congested and purplish 

 and suffused with blood. The blood generally was fluid, but some soft clots were found in the 

 abdominal vessels. 



