634 



REPTILES AND AMPHIBIANS. 



very act of swallowing one about half his own size. I have subsequently 

 seen snakes in the stomachs of other snakes, salamanders in other sala- 

 manders, and it may be an interesting question as to how far "this canni- 

 balistic habit obtains throughout the animal kingdom. 



In the stomach of this same species, Allen* found a Chrysemis picta or 

 Painted Tortoise, one and a half inches long, and saw it seize a cedar 

 bird which he had shot, and which the frog proceeded to swallow, 

 although the wings and tail projected from its mouth, and there it sat 

 waiting quietly for the lower end to digest. The same gentlemen, as 

 well as Dr. Brewer,t states that they have seen it swallow young ducks, 

 and it is a common belief of Massachusetts farmers that it robs them of 

 their young chickens. The story by Dr. Jones J of finding a grass snake 

 in the stomach of a large bull frog is so remarkable that we may reason- 

 ably hesitate about accepting it until confirmed by other observers. 



Other frogs probably use similar food; in fact, the writer has observed 

 the RavM halecina or Leopard Prog in the act of swallowing its own 

 species, and has found the elytra of beetles in their stomachs. And as 

 these animals, as well as toads, lizards, salamanders, and some snakes 

 subsist chiefly upon insects, they aid in keeping down the multiplicity 

 of these pests, and are thus beneficial. 



The tadpoles or young of frogs, and probably also of salamanders live 

 almost, or entirely, upon vegetable matter. However, in some cases they 

 are said to have eaten decomposing animal matter, and even other tad- 

 poles. Prof. Baird states that this may be taken advantage of to clean 

 skeletons by placing the two together in water. The larval Rana sylvatiea 

 he found to be the most effective, as these devoured the macerated flesh, 

 leaving a ligamentous skeleton. Their food primarily is vegetable, and 

 it is probable that they never attack their own species unless driven by 

 hunger or after they have attained a good degree of development. 



The frog is, usually at least, very cautious in regard to its method of 

 taking food. It ordinarily approaches and first touches the prey with 

 its tongue, then retires and afterwards returning with a spring, seizes, 

 holds, and manipulates it dextrously with the fingers of its anterior feet, 

 then closes its eyes, and forces the animal head foremost downwards into 

 the stomach. During this operation, if interrupted, it jerks and kicks 

 vigorously so long as the intruder continues its annoyance. 



The toad is a voracious feeder. It has been observed to eat nine wasps, 

 one after the other, but would take no more. The same afternoon it 



* Proc. Boaton Soo. Nat. Hist., Vol. 12, pp. 185-197. 



tProo. Boston See. Nat. Hist., Vol. 5, p. 211. 



t Chemical and Physical Investigations, Smithsonian Contributions, Vol. 8. 



