172 VENOMS 
found to be coagulated into a mass in all the vessels; it afterwards 
gradually becomes redissolved in six or eight hours, and then 
appears laccate, as after poisoning by Cobra-venom, but darker. 
All mammals exhibit the same symptoms after inoculation with 
lethal doses of venom. The same applies to birds; but in the 
latter the period of asphyxia is much longer, probably on account 
of the reserves of air accumulated in their air-sacs and pneumatic 
bones. They gape like pigeons that are being suffocated, rest the 
tip of the beak on the floor of the cage, and frequently have con- 
vulsive spasms of the pharynx, accompanied by flapping of the 
wings. Small birds and even pigeons are extremely sensitive to 
venom; fowls are more resistant. 
Frogs, thanks to their cutaneous respiration, succumb very 
slowly. I have seen some survive for thirty hours after being 
inoculated with a quantity of venom which, when subcutaneously 
injected into a rabbit, causes death in ten minutes. 
Lizards and chameleons succumb very rapidly. Grass Snakes 
and non-venomous snakes in general withstand doses of venom 
that in proportion to their weight are fairly large; nevertheless, 
as indeed we shall see in the sequel, they do not possess any 
real immunity. It is only poisonous snakes that are unaffected 
by enormous doses of their own venom, as has already been shown 
by Fontana, Weir Mitchell, and Viaud Grand Marais. They are, 
however, quite capable of being poisoned by snakes belonging to 
altogether different species ; strong doses of Crotalus- or Lachesis- 
venom are fatal to Cobras or Kraits, and, when several poisonous 
snakes are shut up together in the same cage, they are not in- 
frequently seen to kill each other as the result of repeated bites. 
Fishes, which are particularly sensitive to the venom of Hypro- 
PHIIDA, readily succumb to inoculation with other venoms, such 
as that of the Cobra. At Saigon, in 1891, I made experiments 
upon the action of this latter venom on two specimens of the 
