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RAYMOND PEARL 



different gametic combinations. The following B.P.R. males 

 were used in these matings. The class and gametic constitution 

 given are those which have been brought out by the pure B.P.R. 

 matings. 



Of these males four, namely 552, 554, 573 and 564, were mated 

 with females whose sire was C.I.G. cT 557. These birds all had 

 the gametic constitution fhU ■ FLik, as shown in the section on 

 the Fi birds. The results of these matings are shown in table 31. 



The observed figures are a rather bad, though not an impossible, 

 approximation to the expected Mendelian half. The means indi- 

 cate, however, that there is a definite segregation of the two classes. 

 It is possible that the discrepancy in the ratio finds its explana- 

 tion in a difference in the potency or absolute fecundity value of 

 the Cornish Indian Game Li factor and the same factor in the 

 Barred Plymouth Rock. 



TABLE 31 



Showing the results of matings of the type B.R.P.d'fULi . fhLi 

 X Black Fi9 fhU ■ FLih 



