HOW TO COLLECT SNAKE VENOM. 377 



of venom from a fresh Indian Cobra. In captivity he found 

 the same species of snakes only yielded from five to ten drops. 



I was holding an average-sized Puff Adder by the neck on my 

 table when, with an unexpected tug, it jerked its head free and 

 aimed a blow at my left hand which I succeeded in jerking away 

 in time. The snake's head struck the table with a loud thump 

 and a quantity of venom was ejected upon the glossy American 

 leather cover. I collected eight drops and calculated that two 

 or three more drops remained which could not be removed from 

 the cloth. The average quantity of venom obtained from a 

 large freshly caught Puff Adder is about ten drops by allowing 

 it to discharge venom voluntarily and by squeezing the glands 

 with the fingers. Puff Adders, after being kept in captivity for 

 two or three months, yield an average of four or five drops of 

 venom. Sometimes only a drop or two can be obtained. I 

 have noticed that when a snake makes a full bite on a living 

 animal, usually no poison oozes out of the punctures. The 

 reason is that the venom is driven into the tissues with great 

 force, and at the same time the punctures are plugged by the 

 fangs, consequently the venom spreads out into the tissues 

 around the wounds. This being so, it is desirable, if an attempt 

 is being made to suck out the poison by mouth suction, that the 

 flesh be previously well scarified over the site of the punctures. 

 Of course, while the knife is being got ready, the punctures 

 should be sucked meanwhile, as this retards the absorbing power 

 of the capillary blood vessels and lymphatics, which lie in a 

 thick network under the skin and among the muscles. 



Snake venom is slightly acid. Sometimes it is found to be 

 more or less alkaline. This is due to admixture with the secre- 

 tions of the mouth. Cobra venom is intensely bitter. Viper 

 venom is more or less tasteless. The specific gravity of Cobra 

 venom, according to Martin, averages ii-io ; that of the Daboia 

 (Indian Adder), 1077. The amount of soHds contained in these 

 two venoms corresponded with the specific gravity — the per- 

 centage of solids in Cobra venom averaged 31 -5 and in the poison 

 of the Daboia 24*4. C. J. Martin states that the variations are 

 considerable in the case of the Cobra, being from 23 to 38 per cent. 

 Pure venom, when examined microscopically, reveals nothing. 

 If it be contaminated with the fluids of the snake's mouth, 

 salivary corpuscles, bacteria, and epithelial cells are seen. 



