CARE OF OFFSPRING 227 



hopeful standing, fully fledged but helpless on its edge. But 

 this reunion is but of brief duration, inasmuch as the youngster 

 is straightway driven off and a new nest is commenced. Never- 

 theless, he seems loth to leave the parental dwelling, remaining 

 in the vicinity for some months longer, but from time to time 

 taking short trips to sea, probably accompanied by one of the 

 parents, who plays the part of instructor. 



Parrots feed their offspring on regurgitated food, and also 

 be it noted, feed one another during the process of courtship, 

 a fact which may throw some light on the origin of this method 

 of feeding the young. The White Stork — and probably other 

 species — feeds its young after this fashion also, placing its beak 

 within that of the nestling during the operation. The members 

 of the Finch tribe, as we have just remarked, feed their young 

 at first on insects, but later on regurgitated seeds. For the 

 preparation of this pabulum green seeds are chosen. The 

 Night- jar feeds by regurgitation, and so also does the House- 

 martin, though the remaining members of the Swallow tribe 

 feed their young on insects. This fact is interesting, showing, 

 as it does, how careful one must be in forming conclusions 

 as to the feeding habits of nearly allied birds based on the ob- 

 servations of a single species. Similarly again, the Green Wood- 

 pecker {Gecinus viridis) regurgitates, while the Greater and 

 Lesser Spotted species retain ^ the more primitive method of 

 rearing their young on the undigested insects. This regurgi- 

 tated food, it should be remarked, differs among different birds 

 in this respect, that whereas in the majority of cases it is injected 

 into the mouth of the chick but little if at all changed, in others 

 it is considerably changed, as in the Petrels and the Green 

 Woodpecker. In the Pigeons again, at least during the earlier 

 period of feeding, the regurgitated food takes the form of a 

 milky secretion — known as " Pigeons' milk " — formed by the 

 disintegration of the mucous membrane of the crop. 



The method of conveying this food also varies. Thus in 

 the Penguin and Cormorant, for example, the young thrusts its 

 head down the throat of the parent ; in like manner the young- 

 Pigeon thrusts its beak within that of the parent, but it would 

 appear that in the case of the Martin the operation is reversed. 

 On this point, however, as in much else that concerns the 

 feeding of the young, more observations are sadly needed. 



