inheritance; of fe:cundity in domestic fowi,. 289 



easy observation and confirmation, that different breeds and 

 strains of poultry differ widely in their laying capacity. Tn say- 

 ing this the writer would not be understood to affirm that a 

 definite degree of fecundity is a fixed and unalterable charac- 

 teristic of any particular breed. The history of breeds shows 

 very clearly that certain breeds now notably poor in laying, 

 qualities were once particularly good. One of the best exam- 

 ples of this is the Polish fowl. But, in spite of this, inheritable 

 breed and strain differences in fecundity exist, and probably 

 always have existed. Such inheritable differences are indepen- 

 dent of feeding or any other environmental factors. Thus 

 the strain of Cornish Indian Games with which T have worked 

 are poor layers, regardless of how they are fed or handled. 

 This is merely a statement of particular fact; it does not imply 

 that there may not exist other strains of Cornish Indian Games 

 that are good layers. 



The difference between this strain of Cornish Indian Games 

 and Barred Plymouth Rocks, when kept under the same condi- 

 tions and managed in the same way, is shown in tables 1 and 2, 

 which give the frequency distributions and constants respec- 

 tively, for flocks of these breeds kept at the Maine Station. The 

 birds included in table i were all pullets, hatched at approxi- 

 mately the same time, and reared, housed, fed and cared for in 

 all respects similarly. The Plymouth Rock distribution includes 

 birds of both high and low fecundity strains. The low produc- 

 ing birds lower the mean in what is really an unfair manner, so 

 far as concerns breed comparisons. The point is that, in the 

 work of the Station, low-producing lines have been propagated 

 for experimental purposes to a much greater extent than v/ould 

 be the case in purely random breeding of the Maine Station's 

 stock of the Barred Plymouth Rock breed. To make a perfectly 

 just comparison between Cornish Indian Games and Barred 

 Rocks, the strains of the latter deliberately bred for low egg 

 production should be excluded. It has, however, in the present 

 case been deemed best to take the whole flock of Barred Rock 

 pullets for the la3dng year 1910-11, without any selection. The 

 comparison is sufficiently striking even on this basis. 



