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Show 282 'HAl'. V liJ. fab:icly asserted that Call-ducln; ltatch their eggs in Jess time than common ducks.1i The Penguin duck is tho most remarkable of all tho br?c~s; tho thin neck and body arc carried erect; tho wings [tro Rmall; tho tm 1 IS ~pturncd; and the thigh-bones and motatar. i arc considerably lon~thcncd m :flroportiou with tho Ramo bones in the wild duck. Iu five spcmmcns cx.ammcd ?Y me there were only eighteen tail-feathers instead of. twenty a~ m the w1~d duck; l>ut I bavo also found only eighteen and run tc?n tail-feathers m two Labrador duckfl. On tho middle toe, in tltrce spccJmcnH, thoro were twonty-scvon or twenty-eight scntcllro, whereas in two wild ducks thc.ro were thirty-one and thirty-two. 'rlto Penguin '~hen :rosscd ~mnsm1~s with much powc1· its peculiar form of body and ga1t ~o 1ts off.spnng; thm was manifc. t with some hybrids raised in the Zoologwal Ga.rdcn~ between one of these birds n,nd tho Egyptian goose 18 ('l'adoma ./lJJgypt~ac~), and likewise with some mongrels which I raised between the Po~gUID and Labrador duck. I am not much surprised that some wnters have 111aintaincd that thi · urced must be descended from an lmlmown and distinct species; but from tho reasons already a ·signc~, it seems to .me far more probable that it is the descendant, much modified by domcstwation under an unnatural climate, of Anus boschus. Osteological Uhrtmctr"l's. - 'l'ho Rkulls of the sovcml breeds differ from each 1.\ l<'ig. 3U.--Sknlls, , 1cw1 u lntcm lly, rednc0d ttl two-thirds or lhe uatuml si~.e. A. Wild Ducic. B. Houk·billcd lJnclc other and from tho skull of tho wild duck in very little except in the proportional length and curvature of tho prcmaxillarics. Those latter bones in the Call-duck arc short, and a line drawn from their extremities to the summit of tho skuJl is nearly straight, instead of being concave as in the 1; 'Uottagc Gnnlcncr,' April Gth, !Sfil. tR Thew hyl!l·irls have been dc:scriberl by M. Sclys-Longchamps in tho 'Bulletins rt01n. xii. No. 10) Aead. Hoy. de Rruxcll cs.' CHAP. VJII. DIFFERENCES IN THmR SKELETONS. 283 common <luck; so that the skull resembles that of a small goose. In the hook-billed duck (fig. 39) these same bones as well as tho lower jaw curvo downwards in a most remarkable manner, as represented. In the Labntdor duck tho premaxillarics arc rather hroader than in the wild duck; and in two skulls of this breed the vertical ridges on each side of tho supra-o cipital bono arc very prominent. In the Penguin the premaxillarics arc relatively shorter than in the wild duck; and the inferior points of tho paramastoids more prominent. In a Dutch tufted duck, the skull under the enormous tuft was slightly more globular and was perforated by two large apertures; in this skull tho lachrymal bonos were produced much further backwards, so as to have a different shape and to nearly touch tho post. lat. processes of the frontal bones, thus almost completing tho bony orbit of the eye. As the quadrate ancl pterygoid bones arc of such complex shape and stand in relation with so many other hones, I carefully compared them in all the principal breeds; but excepting in size they presented no diffcrenc . Ve1·tebl'ce and Ribs.-In one skeleton of tho Labrador cluck there were the mmal fifteen cervical vcrtcbrre and the usual nino dorsal vcrtcbrre bearing ribs; in tho other Rkcloton there were fifteen cervical and ten dorsal vertebrro with ribs; nor, a.· far as could be judged, watl this owing merely to a rib having been developed on the first lumbar vertebra; for in Loth skeletons ille lumbar vertobne agreed perfectly in number, shape, and size with those of the wild duck. ln two skeletons of the Call- c duck thoro were fifteen cervical and 11 nine dorsal vcrtehrro; iu a third skeleton small rills were attached to tho :;o-caUcd fifioonth cervical vcrtcbm making ten pain; of ribs; but those tc1~ l'ig. ~0.-Ccrvlcal Vertcbrw, or 11nturul ribs do not COrrespond, or arise from size. A. Eighth cervicul vertebra of th · same vertchrro, with the ten in tho Wild Duck, viewed on lw~mnl surface. above-mentioned Labrador duck. In B Eighth cervical vertebra of Call Duck, viewed us above. C. Twelfth the Call-duck, which had small ribs cervical vertebm of Wild Duck, vi ewed attached to tho fifteenth cervical ver- latcmlly. D. Twelfth cervical verlebru tebra, tho hremal Rpines of the thirteenth of Aylc,;bury Duck, vi ewed lut.crully. and fourt?cnth ( cc:·vical) and of the seventeenth (dorsal) vCTtchrre corresponded '':'1th tho spmcs on the fourteenth, fifteenth, and eighteenth vcrtebrre of the wild duck: so that each of these vcrtebn:e had acquired a strnctme proper to ono posterior to it in position. Jn tho twelfth cervical vertebra of this same Call-duck (fig. '40, B), tho two branches of the bromal spine stand llluch closer together than in the wild duck (A), and the descending hrorpal processes arc mnch shortened. In tho Penguin cluck the neck from its thinness and Cl' ctncss falsely appears (as ascertained by measurement) to be much clon.gated, but the cervical and dorsal vcrtcbnc present no difference; the posteriOr dorsal vcrtobrro, however, arc more completely anchylo. eel to |