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Show 116 DOMESTIC RABBITS. CIIA I'.lV. uniform habits of life. We cannot account for most of tho differences in the skeleton; . but ,.,-o shall sec that tho increased size of the body, duo to careful nurture and continued soloetion, bas affect >d tho head in a particular manner. Evon the elongation and lopping of the ears have influenced in a small degree the f?rm of the whole skull. Tho want of exorcise has apparently mo<hfied the proportional length of the limbs in comparison with the body. As a standard of compari. on, I prepared skeletons of two wild rabbits from Kent, one from the Shetland Islands, and ono from AntTim in Ireland. As all the bones in these four specimens from such distant localities closely resembled each other, presenting scarcely any appreciable difference, it may be concluded that the bones of the wild rabbit are generally unifonn in character. Slcull.-I have carefully examined skulls of ten h~Xgc lop-cared fancy rabbits, and of five common domestic rabbits, which latter differ from the lop-cared only in not having such large bodies or cars, yet both larger than in tho wild mhbit. First for the ten lop-oared rabbits: in all these the skull is rcmaclw.bly elongated :in comparison with its breadth. In a wild rabbit tb.e length was 3·15 inches, in a large fancy rabbit 4·30; whilst the breadth of tho cranium enclosing the brain was in both almost exactly the same. Even by taking as the standard of com pari. ·on the widest part of the zygomatic arch, the skulls of the lop-cared are proportionally to their breadth three-quarters of an inch too long. The depth of tho head has increased almost in the same proportion with the length ; it :is the breadth alone which has not increased. rrhc parietal and occipital bm:ics enclosing the brain arc los.· arched, both in a longitudinal and transverse line, than in the wild rabbit, so that the shape of the cranium :is somewhat different. The surface is rougher, less cleanly sculptured, and the lines of sutures aro more prmninent. Although the sku.lls of tbc large lop-cared rabbits in comparison with those of the wild rabbit arc much elongated relatively to their breadth, yet, relatively to the size of body, they arc far from elongated. Tho lop-cared rabbits which I examined were, though not fat, more than twice as heavy as tho wild specimens; but the skull was very far from being twice as long. Even if we take the fairer standard of the length of body, from the nose to the anu. ·, tho skull is not on an average as long as it ought to bo by a third of an inch. In the small feral P. Santo rabbit, on tho other hand, the head relatively to the length of body is about a quarter of an inch too long. Th:is elongation of tho skull relatively to its breadth, I find a universal character, not only with the large lop-eared rabbits, but in all the artificial breed·; as is well seen in tho skull of the Angora. I wa · at first much surprised at tho fact, and could not imagine why domestication sboulcl produce th:is uniform result; but tho explanation seems to lie :in the circnmstauee that clming a number of generations the artificial races have been closely coufiuod, ancl have ]tad little occasion to exert either their senses, or iutcllcct, or voluntary muscles; conscCiucntly the brain, as CIIA.P. IV. DIFFERENCES IN TIIETR SKELETONS . 117 ':o shall _presently mora full ~:z~ of body. As tho brain ~a.~c~ ~0:'3 not increased relatively with tho I as not inm·casccl and l . o mcrcascd, tho bony case . the bmiclth of the cnti:·c sk~l~:sfi~: 0e;~d;on!~d.affcctcd through c~~~i~~~~~ Fig. G.-Skull or Wild Rabb't f I ' o natural size. Fig. 7.-Skull of large Lop-eared Rabb"t In all th kt of natural size. I , or . , c s llls of the large Jo -earc , . piOccsses of the frontal bones ~ d mbbits, the supra-ol'bital pJ t and they . are much bro d . th . < a OR posterio. gcncl'~lly project more upwards ~CI th an m the wild rabbit and in t~ or. pl'~Jccting point of the malal:-b . e zygomatic arch th~ o spcmmon, fig 8 it is so . one IS broader and blunter approaches nearer to th~ ~uilit . m a remarkable dcgl'co. This . ; b~ best seen in fig. 8. but thi ?ry meatus than in the wild rabbit aspomt d.irccti f t ' s Circumstance a.:inl d ' < may 8 ?11 0 ho meatus. The inter . m Y cpcnds on the chano·ed j:~b~ ~tho .~>cvoml sl_mlls; gencra~~a:~I~~~~nc (see fi.g. 9) differs much in c of tho longitudinal axis of the k c oval.' or has a greater width s ull, than m the wild rabbit. The |