THE VENOM OF THE AUSTRALIAN BLACK SNAKE. 249 
(2) Some body of the nature of a digestive ferment. 
(3) Alkaloids or ptomaines. 
(4) A crystalline acid. 
(5) Proteids. 
Although grave doubt has been thrown even upon the existence in 
venom of the majority of the above list, and although it has 
further been shown that the active properties of the Indian and 
North American snakes are resident in the proteid constituents 
of these venoms, facts which afford a basis a priorz, for inferring 
that the poisonous qualities of Australian snakes are due to similar 
substances, we yet thought it advisable to exclude the possibility 
of the presence of any poison of another nature. The results of 
our observations and experiments in reference to each of these 
alieged poisonous bodies may now be discussed seriatim. 
(1.) In 1878 Dr. Jean Baptist de Lacerda* of Rio, announced 
his discovery that the effects of snake poison were due to germs 
contained in the venom. ‘To test this statement, snake poison 
was allowed to drop from the fang directly upon a slide, means 
being taken to prevent contamination by saliva. The drop of 
poison was then dried and stained with methyl violet and ex- 
amined for micro-organisms, but with negative result. 
We have also inoculated tubes of nutrient beef broth and gela- 
tine, and of nutrient snake broth and gelatine, with the poison 
and have kept them at 20° C., again with negative result. 
Lacerda does not say how he collected his poison, most probably 
it was contaminated with saliva, which in snakes under some cir- 
cumstances teems with bacteria. When a snake swallows another 
animal, frequently almost as large as itself, the creature swallowed 
undergoes putrefaction as well as digestion, and judging from the 
appearance and smell of the gastric contents in snakes we have 
opened some few days after a meal, one would say that the former 
process was in excess. With such a decomposing mass in the 
stomach it is not surprising that the mouth should be swarming 
* Compt. Rend. Acad. d Sc., Paris, uxxxXvil. 
