Craig, Expressions of Emotion m Pigeons. 



63 



individuals iu which the coo appears very hUe, it is correspondingly 

 well developed when it does appear. 



Development of rlnjflnii and melody. — The modulation of the 

 alarm-note and of the kah being practically of the adult type from 

 the very beginning, these utterances exhibit no development in rhythm 

 or inflection. The coos are the only utterances which go through a 

 long course of development in modulation. 



By the third month, the coo has been extended considerably. There 

 is a greater number of notes, and the notes are, on an average, of 

 longer duration. But even at this time the rhythm is so imperfectly 

 developed, so irregular, that it often bears little resemblance to that 

 in the adult song. Moreover, the rhythm varies so much, even in 

 a single series of coos, that one must conclude it is largely accidental. 

 The following are examples. 



N0.3a, 





kukuku kuKu u uu 



? GOtli day. Nest-call coo. 



Tiiuo: 3 crotchets per second. Attitude: uest-call. Tune very variable. In 



fact, no constant tnne at all. 



N0.33 A 



N0.33B. 



&: 



3 



^s 



^i 



*i 9 l ll' ?a? ?^-M ^ 



ka u kur 



ku ku ku ka u 



N0.33C. 



i^^ 



s 



=^^ 



1 T ^ ■' ■ 11 



ka u kur ka u ku 



(^82nd day. 



1'hough the coo is so formless at first, it very soon begins to show 

 the general form of the adult coo. It comes to consist uniformly 



