284 PROCEEDINGS OF THE ACADEMY OF [June, 



natural behavior. It is highly characteristic of many birds to 

 thresh their prey about, and this is often continued until the object 

 is broken in many pieces, which are separately swallowed. E. B. 

 Poulton considered (P. Z. S., 1887, p. 219) that a pupa would have 

 been swallowed whole if palatable, but as it was crushed and the 

 contents eaten it must have been unpalatable; and Weismann 

 (Studies in the Theory of Descent, 1882, Vol. I, p. 341) thinks it readily 

 conceivable that a certain caterpillar may not be unpalatable to 

 lizards, because they swallow it whole, whilst it is perhaps distasteful 

 to birds, because they must hack and tear it in order to swallow it. 

 As a matter of fact, it is habitual for woodpeckers and jays to peck 

 open pupse and extract the contents, and smaller birds, as the chicka- 

 dees and titmice, not only use this method when attacking pupse, 

 but for large larva? also. Many birds hold the food between their 

 feet and hammer it vigorously before eating, and others accomplish 

 the same end by repeatedly picking it up and throwing it down. 

 At least one experimenter, Jenner Weir, recognized such actions as 

 natural, for he says, "All perfect Lepidoptera apparently require 

 preparation before they are swallowed by birds; they are taken 

 between the mandibles, shaken and bruised for a minute or two, and 

 generally have the wings removed before they are eaten." 6 In many 

 experiments, however, this same action is reckoned . as a sign of 

 disgust, if not as an actual rejection. Lizards habitually chew large 

 prey before swallowing, snakes chew it or crush it by constriction; 

 all of these actions are simply part of the normal preparation of food 

 for deglutition, and in no sense of the word evidences of distaste. 



Hesitancy and caution are usually translated as distaste. Does 

 a bird of prey dislike the mouse it holds by a talon on its perch for 

 hours at a time; does a butcherbird dislike the prey it impales on a 

 thorn or wedges in a crotch for future reference? Does a cat play 

 with a mouse because she hesitates to swallow so distasteful a 

 creature? What animal does not employ dilatory tactics in feeding 

 when it is not uncomfortably hungry? This subject naturally leads 

 up to that of disregard, which may be looked upon as hesitancy 

 prolonged. 



Disregard may arise from many conditions, unrelated to the 

 palatability of the food, such as varying appeal of the food to the 

 captive animal according to its state of activity or health, or degree 

 of hunger; or such as the size of the object offered, presence of the 



8 Trans. Ent. Soc. Lond., 1869, p. 22. 



