SINGLE-COMB WHITE LEGHORN AND HOUDAN. 



23 



of the comb is cleft. A new characteristic of this series of cleft combs is 

 the occasional appearance of a median comb lying between the two wings of 

 the cleft comb — a posteriad continuation of the single part of the comb. 

 This condition appears in three cases (258 $ , 259 ^ , 448 ^ ). It is important 

 for the interpretation of the cleft comb. It gives the posterior part of the 

 hybrid comb the triple condition characteristic of English Houdans, 



The one case that lacks the Y-shaped comb is No. 386 9 (with high 

 nostrils). She has only a pair of papillae. Hurst (1905, p. 133) got no 

 single comb in 105 offspring. 



Second hybrid generation. Fifty-five individuals show the following dis- 

 tribution of comb forms : 



The Y comb being the heterozygous form should appear in 50 per cent of 

 the cases ; each of the other forms in 25 per cent. The deviation from 

 expectation is of the same character as in Series I. That the approximation 

 to theory is less close is probably due to the smaller total number. Hurst 

 (1905, p. 138) obtained 56 ordinary single combs in 226, or 24.8 per cent. 



First hybrid {8y $ ) crossed with white Leghorn (/z $ ). The Y-shaped comb 

 crossed with single gives, in 26 individuals : 



Remarks: Including two cases in which a median ridge runs through 

 the cleft comb. Of these one is a nearly typical pea comb except that 

 the side lobes are higher than the median one. Including, furthermore, 

 one case of an arrow-shaped comb, two parallel V 's occurring in front 

 and behind, respectively, being joined by a median ridge. Including, 

 finally, two cases of cup-comb. 



Here the expected equality is approached. Hurst (1905, p. 139) obtained 

 60 ordinary single combs in 135 individuals of this cross, or 44.4 per cent. 



5, Face Feathering. — First hybrid ge?ieration. Of 24 recorded cases all 

 show the muff (fig. 17). 



