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



to a new and different order of ceremonies, those connected with 

 incubation. 



Throughout the period when the birds are busy dedicating and 

 building the nest, they are busy also with copulation. The sexual 

 act comes only as the culmination of prolonged preliminaries. 

 The caressing and cooing and nest-calling already mentioned all 

 tend to excite the birds; when thus excited, they both show their 

 eros by a certain spasmodic plucking of the inner sides of the wing 

 quills, often referred to briefly as "preening inside the wing"; 

 the female may even beg from the male in very much the same 

 fashion as the young begs from the parent. Finally they bill, 

 the female putting her beak into the mouth of the male and appar- 

 ently receiving a little food thrown up by him from his crop. After 

 billing, the female squats, the male mounts, copulation is performed, 

 and then the copulation-note as already described (p. 400). 



The interval which must elapse between the first copulation and 

 the laying of the first egg, is in the Blond Ring-Do ve about 6 days; 

 in the Mourning Dove it may perhaps be a little less. In the case 

 which I am now narrating the female laid her first egg on July 15, 

 some time between 3:45 and 4:30 p. m.; and her second egg July 

 17, at 7:50 a. m. One egg hatched July 30, early in the morning; 

 the other egg failed to hatch. Male and female take regular daily 

 turns in sitting on the eggs or young : the female sits from evening 

 till morning, the male from morning till evening, the exchanges 

 taking place usually about 8 : 30 a. m. and 4 : 30 p. m. This arrange- 

 ment is very regular if there is nothing to disturb the birds; but 

 if interloping birds come about, this arouses the anger of the male 

 and he leaves the nest in order to attack them. 



During the period of incubation and brooding, the doves are 

 comparatively quiet; in fact their whole temperament is funda- 

 mentally altered. Either male or female, when on the nest incu- 

 bating or brooding, is fearfully quiet, always on the lookout for 

 danger, feathers all appressed, body held low and rigidly still. 

 Yet I have known the female when sitting, to sing her feeble song 

 in answer to her mate; and, each time the sitting bird is relieved 

 by its mate, there is an exchange of little marks of affection, such 

 as flipping the wings, preening the head of the mate, and sometimes 

 a quiet, subdued nest-call. When off and away from the nest, 



