274 FOWLS. Chap. VII. 



tainly become lighter relatively to the leg-bones in all the breeds 

 in which these latter bones are not unnaturally short or delicate ; 

 and that the crest of the sternum, to which the pectoral muscles 

 are attached, has invariably become less prominent, the whole 

 sternum being also extremely liable to deformity. These results 

 we may attribute to the lessened use of the wings. 



Correlation of Growth — I will here sum up the few facts 

 which I have collected on this obscure, but important, subject. 

 In Cochins and Game-fowls there is some relation between 

 the colour of the plumage and the darkness of the egg-shell 

 and even of the yolk. In Sultans the additional sickle-feathers 

 in the tail are apparently related to the general redundancy of 

 the plumage, as shown by the fe atered legs, large crest, and 

 beard. In two tailless fowls which I examined the oil-gland 

 was aborted. A large crest of feathers, as Mr. Tegetmeier has 

 remarked, seems always accompanied by a great diminution or 

 almost entire absence of the comb. A large beard is similarly 

 accompanied by diminished or absent wattles. These latter 

 cases apparently come under the law of compensation or 

 balancement of growth. A large beard beneath the lower jaw 

 and a large top-knot on the skull often go together. The 

 comb when of any peculiar shape, as with Horned, Spanish, 

 and Hamburgh fowls, affects in a corresponding manner the 

 underlying skull ; and we have seen how wonderfully this is 

 the case with Crested fowls when the crest is largely developed. 

 With the protuberance of the frontal bones the shape of the 

 internal surface of the skull and of the brain is greatly modified. 

 The presence of a crest influences in some unknown way the 

 development of the ascending branches of the premaxillary 

 bone, and of the inner processes of the nasal bones ; and 

 likewise the shape of the external orifice of the nostrils. There 

 is a plain and curious correlation between a crest of feathers 

 and the imperfectly ossified condition of the skull. Not only 

 does this hold good with nearly all crested fowls, but likewise 

 with tufted ducks, and as Dr. Gunther informs me with tufted 

 geese in Germany. 



Lastly, the feathers composing the crest in male Polish 

 fowls resemble hackles, and differ greatly in shape from those 

 in the crest of the female. The neck, wing-coverts, and loins 



