404 Craig, Emotion in the Mourning Dove. [.Oct. 



B. The Expressional Life-History. 



The preceding pages on the forms of expression have given but 

 little information as to the uses of expression, for these uses can be 

 understood only in connection with the life-history of the species. 

 The life-history can be given here merely in outline; further de- 

 tails can be found in the numerous biographies of the Mourning 

 Dove, in the paper on ' The Voices of Pigeons regarded as a Means 

 of Social Control' (Craig, 1908), and also in the paper on the Blond 

 Ring-Dove (Expressions in Pigeons. I), for the life-histories of 

 the Ring-Dove and Mourning Dove are fundamentally alike. 



First, a few remarks on the development of the young. The 

 young Mourning Dove even in his squeaking is far more musical 

 than other pigeons; for the begging note of most young pigeons 

 is burred and querulous, but the cry of the young Mourning Dove 

 is a musical sibilant, sliding up the scale, and easily imitated by 

 whistling sssst. Gates, in his very interesting paper (1909, p. 11), 

 shows that the young acquires the adult song in a gradual and 

 progressive manner. Nevertheless, the song is not acquired by 

 imitation (Craig, 1908, pp. 89-91); pigeons seem totally devoid 

 of that power of mimicking or mocking which is so wide-spread 

 among the Oscines. 



The breeding habits of the Mourning Dove as they appear to the 

 ordinary field observer have been described so many times that a 

 repetition of field observations is here unnecessary; I shall treat 

 preferably those details of behavior which can be better observed 

 in the aviary than in the field. As a basis of the narrative I shall 

 tell the story of a pair of captive birds kept in my room, under 

 constant observation, in the summer of 1902. 



A pair of Mourning Doves from Professor Whitman's aviary 

 were brought to my room in the month of June. Whether they 

 had reared a brood earlier in the year, I do not know; but in any 

 case the removal to strange quarters naturally interfered with the 

 continuity of their family life, and it was many days before they 

 became amorous again. The male was a little wild, and cooed 

 but seldom. The female was more tame and contented, and it 

 was she who at length caused the bursting forth of the passion that 

 was but smoldering in both their breasts. For on July 2, at 11:17 



