52 PHYSIOLOGY AND TOXICOLOGY 



allow the question to remain without farther answer, I made a number of experi- 

 ments upon the ability of seeds to germinate in the venom, hoping to obtain in this 

 manner a more complete solution of my doubts. 



Here, owing to the circumstances of the experiment, the result may again be a 

 negative one, and may still be open to all the doubts which encumber negative results. 



Exjyerimenf. — October 5th, 9 A. M. I placed in each of two short test-tubes 

 eight drops of water, and to one of them added one and a half drops of venom of 

 known activity. On both tubes, upon the surface of each of the fluids, I laid a 

 mesh of cotton wool, and upon it in each vessel fifteen canary seeds. The water 

 in the two tubes was kept always at the same level, by the daily addition of the 

 requisite amount of fluid. On the ninth day, none of the seeds in the venom had 

 germinated, while two in the water were sprouting. 



Twenty-one days after the observation began, the venom-tube offered no signs 

 of seed-growth, and smelted very unpleasantly. The germs in the water were nearly 

 half an inch in height. 



As the small number of seeds which germinated in the water made it possible 

 that none but incapable seeds might have fallen to the share of the venom-tube, I 

 repeated the experiment without other variation of the circumstances than the 

 substitution of mignionette seed for those last employed, and the use of a bell glass 

 to limit the too rapid evaporation. Twenty seeds were allotted to each vase. This 

 observation began Oct. 15tli. On Oct. 24th, none of the seeds in the venom cap- 

 sule had sprouted, while three of those in the water were in healthy bud, and some 

 a little above the mesh of cotton. One additional test was required to add to these 

 observations all the strength that could be given to them. It was possible that 

 the venom, in decomposing, had lost its potency, and, as detailed previously, I 

 tested it on animals, but still found it actively poisonous. At various times these 

 experiments were again and again repeated, with slight modifications, but with no 

 other result than continual failure to germinate on the part of seeds put in con- 

 tact with venom. 



It appeared probable from these observations, that venom has the power to 

 prevent the germination of the seeds of plants such as those which 1 have mentioned 

 above. 



Action of Venom on Animal Life. — We have now reached a point where we turn 

 from the influence of the venom upon vegetables, to study its power to affect animal 

 existence. 



In place of doubtfully deciding as to the cause of death, we are summoned to 

 witness the operations of a substance which sometimes acts with a potency so swift 

 as to defy observation, and which has a power to alter the blood and tissues in a 

 manner, and with a celerity, which is a source of unending wonder, even to one 

 who, by daily repetitions, has become familiar with the changes thus produced. 



In the course of study now before us, I shall examine, as fully as possible, the 

 effect of the venom upon cold-blooded animals, including the Crotalus, and upon 

 various classes of warm-blooded animals. 



After this general survey of the symptoms and pathology of the acute and 

 chronic forms of venom poisoning, in these various classes of animals, I shall ex- 



