88 Maine: agriculturai. experiment station. 1910. 



Tabee 3. 



Showing the Sex and Color Pattern of Hybrids Obtained by 

 Reciprocally Crossing Barred Plymouth Rocks and Cornish 

 Indian Games. 





Total 

 offspring. 



Adult Offspeing. 







Barred. 



Non-barred ; 







6 



"3 



a 



Black. 



■ Mating. 



c 

 s 

 S 



6 

 "3 



a 





6 





112 

 127 



111 



124 



70 

 95 



68 



- 







Cornisli cf x Barred Kock $ 



96 







Totals 



239 



235 



165 



68 



_ 





96 











It is clear that we have here a case of sex Hmited inheritance, 

 in which a character is correlated with sex in a definite manner. 

 It was suggested some time ago by Spillman* that barred color 

 pattern in poultry would be found to be inherited in this sex 

 limited manner. This suggestion has been tested and, in a 

 brief preliminary paper, confirmed by Goodale.** 



A Mendelian hypothesis, which may or may not be true, has 

 been put forth by Spillman (loc. cit.) to account for facts re- 

 garding the inheritance of barring given above. This hypo- 

 thesis has been stated in briefest form by Goodale (loc. cit.) 

 as follows : "The barring factor and sex in poultry are corre- 

 lated in such a way that the female is always heterozygous in 

 respect to sex and also barring when present. The male, on 

 the other hand, is always homozygous in respect to sex and 

 may be either homozygous or heterozygous in respect to bar- 

 ring." Further, it is assumed that "femaleness" and the bar- 

 ring factor do not exist together in the same gamete. This can 

 be easily represented symbolically. 



^Spillman, W. J. Barring in Barred Plymouth Rocks. Poultry, Vol. 

 5, No. II, August, 1909, pp. 7, 8. 



Spurious Allelomorphism ; Results of Some Recent Investiga- 

 tions. Amer. Nat. Vol. XLH, pp. 610-615, 1909. 



**Goodale, H. D. Sex and its Relation to the Barring Factor in Poul- 

 try. Science, N. S., Vol. 29, No. 756, pp. 1104, 1105. 1909. 



