Craig, Expressions of Emotion in Pigeons. 65 



the sense of copying thein, or learning new sounds. The forms of 

 utterance (herein the pigeons ditier from many other birds) are 

 strictly hereditary. 



The charge. — The charge is associated in its development with 

 the kah, as has already been stated (page 40), and thus appears at 

 an early age, even at the age of twenty-seven days. The charging 

 activity in the young, as in the adult, includes chasing another bird, 

 pecking her (or him), assuming the peculiar horizontal attitude, 

 progressing by leaps as well as by steps, and uttering the kah (kah- 

 of-excitement). But each of these acts is at first of a weak and gentle 

 sort. The charging activity, like the vocal activities, passes through 

 a prolonged and gradual development before it reaches the form 

 seen in the adult. 



Development of certain other instincts. — Since the first attempts 

 at cooing appear at an age of from twenty-seven to forty-seven days, 

 it might seem that they are too early to have any sexual significance 

 whatever. Yet some activities connected with sex begin at an 

 equally early age, — sitting on eggs, for example. In one instance, 

 on the twenty-first day, a fresh egg having been laid by the mother, 

 the young one entered the nest, observed the egg intently, and care- 

 fully sat on it. At fifty-one days, a young one entered the nest, 

 settled very carefully on the pair of eggs, sat for several minutes, 

 and when the father tried to drive it off persisted for a considerable 

 time in holding its position. This sitting on the eggs is not an ac- 

 cident, for the little fellow is very careful to have the eggs under him, 

 and if there are two eggs he takes a great deal of pains in tidying to 

 get them both under, finally settling down upon them with that side- 

 wise rocking movement always seen in the case of the adult. 



A young female showed the courting propensities of her sex, 

 practising the art upon her father, at a very early age. It is difiicult 

 to say at just what age this began, because it is impossible to draw a 

 sharp line between filial and amorous attentions. At fifty-six days 

 this young female responded to the cooing of the father and some 

 other pigeons by assuming the nest-call attitude, head down and 

 wings shaking, and making an attempt at the nest-call coo. At sev- 

 enty-four days she showed the typical courting behavior, for in the 



