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Show 268 FOWLS. CHAP. VII. Rcvoral other broods examined by me. On tho dorsal ~urfaco of tho sixth cervical vcrteln·a in Cochins throe prominent pomts arc more strongly developed than in tho corresponding vertebra of the Game-fowl or a. banl.-i va. ] 1 t 'l'h J'dvis.- This differs in some few points in tho several s.rc e on~. e anterior margm· of t 1t e 1·1 :m m seems. a t fui ·st to vary. m. uch m .o utlmc, .b u. t this is chiefly duo to tho degree to which the margiD m tho U:1~dl~ pat~ JS ossiftocl to tho crest of tho spine ; tho outline, however, doc~ differ m bon~ g more truncated in Bantams, and more rounded in cm·tau~ broods, as. 111 Cocltins. Tho outlillo of tho ischiadic foram en cliffors. oonmdcmbl!, homg nearly cJ· rCltlar m· Bantams, m· st , oa d o f' cg g- shaped as m tho Banlnva, and moro regularly oval m· some sk o1 o t ons, as· J·n tho S• panish. . The ob, tura, t, or notch i. also mnch Joss elongated in some skeletons than 1 ~ other s. lho end of the pubic bono pro. ents tho greatest clifl'eronce; ~mg. hardly _on,largod in the Bankiva; considerably and gradually onhtrgod m Coch1D:s, and in a lessor dop;reo in some other breeds; and ~brnptly enlarged m Bantams. In one Bantam this bono extended very lltt~o be~ond th~ extremity of tho ischium. Tho whole pelvis in t~s latter bi.rd chff~rod w1do~y in its proportions, being far broader proportwnally to Its lonoth than m Bankiva. · · 1 , 'tm·num.-This bono is generally so much deformed that It IS scarce Y. possible to compare its form strictly in tho sevoml breod.s. The shape of tho triangular extremity of the lateral processes differs considerably, being either almost cqnilatoral or much elongated. Tho front margin of tho crest is more or less perpendicular and varies greatly, as docs the curvature of tho posterior end, and tho flatness of tho lower surface. 'l'ho outline of the manubrial process also varies, being wedge-shaped in the Banki va, and rounded in tho Spanish brood. The j m·culn differs in being more or le~s B c arched, and greatly, as may be soon m ~~~~., tho accompanying outJjnos, in tho shape of tho terminal plato; but tho shape of this part differed a little in two skeletons of the wild Ban.kiva. Tho comcoids prosent no difference worth notice. Tho n sc!qnr ln varies in shape, l>eing of nearly uniform breadth in Bankiva, much broader in tho middle in the Polish Fig. a~.- Extr0mity of the Fm cnla, of' fowl, and abruptly narrowed towardS 1mtuml ~ i zc, vi ewed lttlcrully. A. Wilt! f 1 (.'al/us bankiva. B. Spangled J'u llob the apex in tho two Sultan ow s. Fowl. u. Spanish Fowl. D. Dorklug I ca1·ofully compared each separate Fowl. hone of tho log and wino·, relatively to tho same bonos in tbo wild Dankiva, in tho following breeds, w~ich l thought were tho most likely to differ; namely, in Cochin, Dorking, C HAP. VII. OSTEOJ~OGICAL DIFFERENCES. 269 Spanish, Polish, Burmese Bantam, Frizzled Indian, and black-honed Silk fowls; and it was truly surprising to soo how absolutely every process, articulation, and pore agreed, though tho bonos differed greatly in size. The agreement is far more absolute than in other parts of tho skeleton. In stating tllis, I do not refer to tho relative thickness and length of tho several hones ; for tho tarsi varied considerably in both these respects. But tho other limb-bonos varied little even in relative length. Finally, I have not examined a sufficient number of skeletons to say whether any of the foregoing differences, except in the skull, are characteristic of the several breeds. Apparently some differences are more common in certain breeds than in others,-as an additional rib to the fourteenth cervical vertebra in Hamburghs and Games, and the breadth of the end of the pubic bone in Oochins. Both skeletons of the Sultan fowl had eight dorsal vertebrro, and the end of the scapula in both was somewhat attenuated. In the skull, the deep medial furrow in the frontal bones and the vertically elongated occipital foramen seem to be characteristic of Oochins; as is the great breadth of the frontal bones in Dorkings; the separation and open spaces between the tips of the ascending branches of the premaxillaries and nasal bones, as well as the front part of the skull being but little depressed, characterise Hamburghs; the globular shape of the posterior part of the skull seems to be characteristic of laced Bantams; and lastly, the protuberance of the skull with the ascending branches of the premaxillaries partially aborted, togeth0r wjth the other differences before specified, are eminently characteristic of Polish and other Crested fowls. But the most striking result of our examination of the skeleton is the great variability of all the bones except those of the extremities. To a certain extent we can understand why the skeleton fluctuates so much in structure; fowls have been exposed to unnatural conditions of life, and thejr whole organisation has thus been rendered variable; but the breeder is quite indifferent to, and never intentionally selects, any modifications in the skeleton. External characters, if not attended to by man,-such as the number of the tail and wing feathers and their relative lengths, which in wild birds are generally com;tant points,-fluctuate in our domestic fowls in the same manner as the several parts of the skeleton. An additional toe is a " point" in Dorkings, and has become a fixed character, but is variable in |