19*21.] Poultry Reskabch. 



Factors controlling Artificial Incubation. There would be 

 little difficulty in indicating problems the solution of which 

 would greatly benefit the poultry industry. All those questions 

 that centre around artificial incubation immediately suggest 

 themselves, and it is, indeed, fortunate that a start has been 

 made in this direction. So far as present indications go, 

 Professor Chattock is in a fair way of revealing some of the 

 factors controlling successful artificial incubation. Being 

 artificial, it is reasonable to surmise that the factors are many, 

 and it may be safely predicted that, the deeper the problems are 

 probed the more widely will their ramifications be found to < \- 

 tend. New questions are bound to present themselves, but while 

 these are waiting for answers, those solutions that have already 

 been arrived at are available for practical application. 



Avian Reproduction. — The phases of reproduction prior to 

 incubation also offer wide scope for the investigator. While 

 there are principles of the physiology of reproduction common 

 to all the higher animals, there are many features of repro- 

 duction peculiar to birds. Obviously, phenomena long recog- 

 nised and subjected to investigation in mammals must of 

 necessity be absent in oviparous animals; and phases of the 

 reproductive act that are of first importance in birds are incon- 

 spicuous in mammals. Seeing that the ovum of birds, as first 

 formed in the ovary, is so small, it is evident that the forma- 

 tion of the other components of the egg — the yolk and the 

 white — and the laws governing their formation, must always 

 stand first in economic importance. The periodic production 

 of relatively enormous quantities of albumen by the fowl 

 has no exact parallel in the mammal. Clearly, then, the 

 general and mammalian physiologist can scarcely be expected 

 to give special attention to such processes, though they lie 

 at the very root of success in the poultry industry. Not that 

 the physiology of avian reproduction has been entirely 

 neglected: much attention has been paid to it by American 

 investigators. Yet no one with a knowledge of research work< re 1 

 publications can escape the conviction thai what has been dis- 

 covered in this direction is but a tithe of what remains to 

 be discovered before any practical application of the know- 

 ledge is possible. 



Problems of Reproduction. — With the problems of reproduc- 

 tion as affecting egg-production, those of heredity are inseparably 

 connected. The utility poultry keeper is probably not very 

 interested in fine distinctions of plumage or in the size and shape 



