266 THE REASON WHY : 



Whilst wheeling round in airy wanton flights, 



The glossy pigeons chase their sportive loves.&quot; DODSLEY. 



ORDER IV. GYRATORES. 



832. Why is the order gyratores thus designated ? 



From the word gyratio, a &quot; turning&quot; or &quot; wheeling round.&quot; It 

 refers to the ordinary mode of flight displayed by the birds 

 included in the order. 



833. Why has the pigeon tribe a puffed-out appearance 

 about the breast ? 



This arises from the presence of its unusually large crop ; an 

 organ which is capable of some of the uses of the paps 

 in mammalia. 



834. By what remarkable process are the young pigeons and 

 other birds of the dove-kind fed by their parents ? 



The parents of the dove kind support their young with the 

 curd-like contents of their crops, as the mammalia do with milk 

 in the early stages of the existence of their offspring. 



835. This is performed by the faculty which the parent birds possess of throwing 

 up the contents of their crops, which assume the appearance of a granulated white 

 curd. It would appear that the young pigeon is fed for a little time Avith this 

 cui d-like substance only, for about the third day some of the common food is found 

 mingled Avith it. As the pigeon grows older, the proportion of common food is 

 increased ; so that, by the time it is seven, eight, or nine days old, the secretion of 

 tne curd cea?es in the old bird, and of course no more will be found in the crop of 

 the young. It is a curious fact, that the parent pigeon has, at first, a power to 

 throw up this curd without any mixture of common food, although, afterwards, 

 both are thrown up according to the proportion required for the young ones. 



No young birds are in so forlorn a state as young pigeons, if the parents are killed 

 before the young can provide for themselves. Birds of other species, stimulated 

 by the cries of the helpless young which have been deprived of parental aid, can 

 and do assist the little starvelings ; but none except an old pigeon, with its crop in a 

 proper state, can save the life of a nestling dove. 



836. Why is the plumage of the rock pigeon very close 

 and compact? 



They are thus furnished to enable them to encounter the s&wrt 



