190 HABITS OF BIRDS. 



young; though, in the instance of pigeons and some 

 others, there exists a provision very similar to that of 

 milk in quadrupeds. 



" I have,'* says John Hunter, ' in my inquiries 

 concerning the various modes in which young ani- 

 mals are nourished, discovered that all the dove kind 

 are endowed with a similar power. The young 

 pigeon, like the young quadruped, till it is capable of 

 digesting $he common food of its kind, is fed with a 

 substance secreted for that purpose by the parent 

 animal ; not as in the mammalia, by the female 

 alone, but also by the male, which perhaps furnishes 

 this nutriment in a degree still more abundant. It 

 is a common property of birds, that both male and 

 female are equally employed in hatching and in feed- 

 ing their young in the second stage ; but this parti- 

 cular mode of nourishment, by means of a sub- 

 stance secreted in their own bodies, is peculiar to 

 certain kinds, and is carried on in the crop. 



" Besides the dove-kind, I have some reason to 

 suppose parrots to be endowed with the same 

 faculty, as they have the power of throwing up the 

 contents of the crop arid feeding one another. I 

 have seen the cock paroquet regularly feed the hen, 

 by first filling his own crop, and then supplying her 

 from his beak. Parrots, macaws, cockatoos, &c., 

 when they are very fond of the person who feeds 

 them, may likewise be observed to have the action of 

 throwing up the food and often do it. The cock 

 pigeon when he caresses the hen, performs the 

 same kind of action as when he feeds his young; 

 but I do not know if at this time he throws up any 

 thing from the crop. 



" During incubation, the coats of the crop in the 

 pigeon are gradually enlarged and thickened, like 

 what happens to the udder of females of the class 

 mammalia, in the term of uterine gestation. On 



