74 INHERITANCE IN POULTRY. 



skin is crossed with white, black the new, positive, pathological character- 

 istic is dominant (page 60). 



MANDIBLE COLOR. 



The prevailing types are black, willow, yellow, and white. Black is the 

 primitive color on the Jungle side ; yellow, on the Aseel group. When horn 

 (Houdan) and yellow (Leghorn) mandible colors are crossed, the first genera- 

 tion shows the yellow of the Leghorn, which is dominant. When, however, 

 the black beak of the Minorca was crossed with the yellow beak of the 

 Brahma, the dark color dominated. The potency in the hybrid of beak color 

 seems to follow this series: Black, yellow, horn. The most positive char- 

 acter, black, dominates all. 



FOOT COLOR. 



Four principal types are to be distinguished willow, black, yellow, and 

 white. Willow is primitive and white the most aberrant. The results are 

 based on still insufficient data, but so far as they go they indicate that willow 

 is dominated by yellow (p. 54), yellow by white (p. 24), and white by black 

 (p. 28). The newer, negative characteristic, white, is dominant over the 

 older yellow, but the new, positive characteristic of melanism dominates all. 



IRIS COLOR. 



Of the various forms, pearl to yellow is characteristic of the Aseel type ; 

 red, of the Game or Gallus bankiva type. Black has become associated with 

 black plumage. The results, subject to revision, indicate that in poultry, 

 as in man, iris color rarely blends, that red dominates pearl (page 38), and 

 that dark brown dominates red. The new, positive variation of melanism 

 seems to dominate all, although not always perfectly. 



EARLOBE COLOR. 



Red is primitive in both groups. White is a new variation, which is prob- 

 ably due to fat or other particles in the skin, and is consequently positive. 

 Only in extreme cases is red wholly eliminated from the earlobe. In three 

 series of crosses (V, VI, and X) of the red-lobed Dark Brahma and a white 

 (and red) lobed race the earlobes were prevailingly red, but had some white 

 at their centers. Likewise, in two series of crosses (VII and VIII) of the 

 red-lobed Cochin and a white-lobed Leghorn, red dominated in the hybrids, 

 but did not always perfectly exclude white. Red is apparently dominant, 

 but very imperfectly so ; some cases rather indicate particulate inheritance. 



GENERAL PLUMAGE COLOR. 



The original plumage as exhibited in the Jungle fowl is largely black and 

 red ; that of the Aseel type sometimes contains much white ; but the pure 

 white plumage must be regarded as a new negative variant. The outcome 

 of crossing is complex. 



