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Show 274. FOWLfl. CHAP. Vll. tainly become lightm· relatively to the log-bones in all the breeds in which these latter bones arc not unnatnra1ly short or delicate; and that the ere t of tho sternum, to whi ·h the pectoral muscles arc attach d, has invariably become less prominent, the whole sternum being also xtromely liable to deformity. The~:~e results we may attribute to the los enod use of the wings. Correlation of Growth.-! 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. ln Sultans tho additional sickle-feathers in the tail are apparently related to the general redundancy of the plumage, a shown by tho feathered leg·, large crest, and beard. In two tailless fowls which I examined the oil-gland was aborted. A large crest of feathers, as Mr. 'fegetmeier has remarked, seems always accompanied by a great diminution or almost entire absence of the comb. A largo beard is similarly accompanied by diminished or absent wattles. These latter cases apparently como 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, afi'ects 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 tho 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 Fome 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 clucks, 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. 'fhe neck, wing-coverts, and loins CHAP. VII. • CORRELATJ ON OF GROWTH. 275 in the male bird . 1 would appear tba~ f:Ia~h~~~poet [hi:o~ered hwith hackles, and it lation to the head of the " ~pe. ave spread by corre-because though b th male. lhJs little fact is interesting ; have th'e ir head o· . sexes of some wild 11' 1 1 ga maceous birds difference in tl s Sl~l ar y ornamented, yet there is often a ~ 1e s1ze and shape f :D h . crests. Furthermore th . . . 0 eat ers formmg their and in the male Amhe e;e ~s m some cases, as in the male Gold close relation in col r~ p eas~lnts (I!· pictus and Amherstii), a plumes on the head omd as who as m structure, between the that the ~arne l han on t e loins. lienee it would appear . aw as reQ'Ulated th t t the bead and body, both wfth s . e .s .a e of the feathers on conditions, and with b · d ·h~ehCies hvmg ?nder their natural t ca w. n. Ir 8 " lC have vaned under cl omest1·- ·r 2 |