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Show 74 DOMESTIC PIGS. CIIA'P. Ill . length may be clue either to descent from a distinct species or to more ancient domestication. The number of mammre vary, as does the period of gestation. The latest au~~ority sa~s 21 that "the period averages from 17 to 20 week~, but I tl~m~\: there must be some error in this statcm nt: m M. Tcs ·wr s observations on 25 sows it varied from 10D to 123 days. The Uov. W. D. Fox has given me ten carefully recorded cases with well-bred pigs, in which the period varied from 101 to 116 days. According to N athusius the pe~·iocl is shortest in the races which come early to maturity; but m these latter tho course of development docs not appear to be actually shortened, for the young animal is born, judging from th~ state ~f. th~ skull, less fully developed, or in a more ombryomc conditiOn, than in tho case of common swine, which arrive at maturity at a later age. In the highly cultivated and early matured races, the teeth, also, arc developed earlier. The difference in tho number of the vertobrm and ribs in different kinds of pigs, as observed by Mr. Eyton,23 and as given in the following table, has often been quoted. The African sow probably belongs to tho S. scroja type ; and Mr. Eyton informs me that, since tho publication of his paper, cross-bred animals from the African and English races were found by Lord Ilill to be perfectly fertile. English Long-1 ggcd Male. Afi·ican Female. Chinese Male. French Wild Ooa1·, Domestic from Cuvicr. Boar, from Cuvior. ------------------------------ Dor al vcrtcbrro Lumbar .. 15 6 13 6 15 4 14 5 14 5 Dors:tl and l.u.m b n.I_.}_;--_19_ __1!_) __I D _ J:D_ together Sacral 5 5 4 4 4 Total num bor o.. f } vcrtebrro .. 2G 21 S. Sidney, ' Tho Pig,' p. 61. 22 'Schweincscbiicld,' s. 2, 20. 24 23 • Proo. Zoolog. Roc.,' 1837, p. 23. I hrtvo not given tho caudal vortobrro, f\8 Mr. Eyton says somo might pos. ibly have b on lost. I have ndtled tog ther the dorsal and lumbnr verlcbrro, owing 23 23 23 to Prof. Owen's remarks (' J ournal Linn. Soc.,' vol. ii. p. 28) on tho difference between dorsal and lumbnr v<:rfobrro dcp n11ing only ou tl1 deve lopment of the ribs. Nevertheless the diflcrence iu Ll1o number of tho ribs in pigs deserves notice. CHAP. III. TIJETl A R1 A TlO .. 7() om , emi-monstrons brc('ds dt rn <' nol i('t'. 11,l'Om the (,i mo of Ari tot] to thr pres 'nt time• solid-hooli'tl ~)Win{ lu~vo of·c;a-ionally be n obsC'rnd in Y1H'ion2 pnrt ' of th wol'ld. A I Ll1ou~h thi p ruliarity i~ , tr ngly inh rih'd it, i hn.nlly pi'OlmiJio that all the animals '"ith solid h ofs have d s ndcd frorn the ~am pur nt · it i mor pnbn.blc that th am p ruliurity hu reapp arcd at variou time nnd pln s. Dr. truth rs ha~; lately d crib d and fi()'urecl 21 the tru tur of tho feet; in both front and hind feet the eli tal phalanges of tho two greater toes arc represented by a single, groat, hoof-bearing phalanx; and in tho front feet, the middle phalanges are represented by a bone which is single towards the lower end, but bears two separate articulations towards the upper end. From other accounts it appears that an intermediate too is likewise sometimes superadded. Another curious anomaly is offered by the appendages, described by lVI. Eudcs-Deslongchamps as often characterizing the Normandy pigs. These appendages are always attached to the same spot, to the corners of tho jaw; they are cylindrical, about three inches in length, covered with bristles, and with a pencil of bri 'ile ri in()' out of a sinus on one side: they have a cartilaginou centre, with two small longitudinal muscles ; th y occur either ymmetrically on both sides of the face or on on 2-l ' Edinhnr~h 'I;W J'}JJ)t,-•IJJ•I• Journal,' AJiril JH(j:l. Htrl s.J"'' lh l: ls11wrifl• ~ ' ( '" '""IIIII Jdii P,' jl I V:, hll •:ttlt/11 wdl11tilfl• 1>1111 ldtiR Rlt lll•'l 1f |