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PROCEEDINGS OF THE ACADEMY OF [June, 



to which they are unknown in the wild state. The experiments of 

 Pocock and Butler, resulting in the acceptance of many British 

 insects by a variety of foreign mammals and birds, illustrate the same 

 point. As noted before, the acceptance of butterflies by some of 

 Finn's birds signifies no more, concerning their natural food habits, 

 than does their acceptance of boiled rice. It means no more than 

 the eating of silver fish, clothes moths, and mealworms by Mrs. 

 Nice's bobwhites. 



The point need be no further elaborated. We are forced to 

 conclude that acceptance of various items of food by captive animals 

 is no indication whatever that they are eaten by the same species 

 in the wild state. 



(2) Rejections. — This point really follows from analogy the con- 

 elusion just cited. There is no logic in regarding rejections as 

 indicative of natural tastes, when acceptances are plainly shown not 

 to be. But evidence to prove the case is much harder to obtain, 

 and it is for this reason that we have been compelled to endure the 

 style of argument that asserts " refusal .... is trustworthy evidence 

 of unpalatability, while acceptance is not proof of palatability." 



Fortunately, however, we have information regarding the choice 

 of food by a number of animals, both in captivity and under natural 

 conditions. We have shown that in certain of the experiments with 

 amphibia, the animals refused articles of food which they habitually 

 eat in the natural state. For instance, this is true of the refusal 

 by the common toad of the Eastern United States of millipeds 

 (Julus), squash-bugs (Anasa tristis), and potato beetles (Leptino- 

 tarsa decemlineata) . Prof. Whitman found that ordinary articles 

 of the natural diet were refused by captive Necturus. Snakes, in 

 particular, often refuse all food in confinement. Is this "trustworthy 

 evidence of unpalatability?" The writer had the care for a year of 

 six prairie rattlesnakes (Sistrurus catenatus). Live mice and birds 

 put in their cage were killed, but not eaten. No food was taken 

 naturally and they were kept alive only by putting meat well down 

 their gullets with long-jawed forceps. 



Beddard found that a green woodpecker made great objection to 

 eating a single earwig, yet Newstead found twenty-three of these 

 insects in the stomach of a wild bird of this species. Finn found 

 that captive red-whiskered bulbuls refused Acrcea, but an observer 

 in India saw the birds feeding the "most distasteful" insect of the 

 genus to their young. So little is known regarding the natural food 

 of birds in most countries that few such comparisons can be made. 



