TOO WALLACE CRAIG. 



toward this end situation does the "chain" of flight reactions 

 take place. 



6. In the pigeons the order of activities culminating in the 

 sexual act is, first display, second billing, third copulation, with 

 numerous details each finding a place in the succession. Yet the 

 sexual tendency is mainfestly present from the beginning of the 

 "chain," and the preliminary steps are directed, with much 

 guidance by experience, toward securing the stimulation re- 

 quired for discharging the sexual reflex. In absence of the normal 

 stimulus to the consummatory reaction, the instinct manifests 

 itself in marked appetitive behavior, and, especially in inex- 

 perienced birds (Craig, '14), in those imperfect consummatory 

 reactions known as perversions and auto-erotic phenomena. 

 The behavior of the sexual appetite is now so well known that 

 it may be cited as the type of appetitive behavior; and to readers 

 who are familiar with modern analyses of the sex instinct I may 

 make my whole article clearest by saying that all the appetitive 

 mechanisms I have mentioned, and I believe all the instincts of 

 the dove, behave in the same manner as that of sex, in regard to 

 appetitive manifestations and anticipation of the consummatory 

 reaction. 



7. I shall take space to describe only one example of aversion 

 the so-called jealousy of the male dove, which is manifested 

 especially in the early days of the brood cycle before the eggs are 

 laid. At this time the male has an aversion to seeing his mate 

 in proximity to any other dove. The sight of another dove near 

 his mate is an "original annoyer" (Thorndike, '13, Chap. IX.). 

 If the male sees another dove near his mate, he follows either of 

 two courses of action; namely, (a) attacking the intruder, with 

 real pugnacity; (6) driving his mate, gently, not pugnaciously, 

 away from the intruder. When he has succeeded either in con- 

 quering the stranger and getting rid of him, or in driving his mate 

 away from the stranger, so that he has got rid of the distuibing 

 sight of another dove in presence of his mate, his agitation ceases. 

 If we prevent him from being successful with either of these 

 methods, as, by confining the pair of doves in one cage and the 

 third dove in plain sight in a contiguous cage, then he will con- 

 tinue indefinitely to try both methods. If we leave all three 



