Chap. XIII. KE VERSION. 17 



that the ass aids in giving, through the power of reversion, this 

 character to its hybrid offspring. 



The quagga is banded over the whole front part of its body like 

 a zebra, but has no stripes on its legs, or mere traces of them. But 

 in the famous hybrid bred by Lord Morton, 35 from a chestnut, 

 nearly purely-bred, Arabian mare, by a male quagga, the stripes 

 were " more strongly defined and darker than those on the legs of 

 " the quagga." The mare was subsequently put to a black Arabian 

 horse, and bore two colts, both of which, as formerly stated, were 

 plainly striped on the legs, and one of them likewise had stripes on 

 the neck and body. 



jLbe Equus indicus 36 is characterised by a spinal stripe, without 

 shoulder or leg stripes ; but traces of these latter stripes may occa- 

 sionally be seen even hi the adult; 37 and Colonel S. Poole, who has 

 had ample opportunities for observation, informs me that in the 

 foal, when first born, the head and legs are often striped, but the 

 shoulder-stripe is not so distinct as in the domestic ass ; all these 

 stripes, excepting that along the spine, soon disappear. Now a 

 hybrid, raised at Knowsley 38 from a female of this species by a 

 male domestic ass, had all four legs transversely and conspicuously 

 striped, had three short stripes on each shoulder and had even some 

 zebra-like stripes on its face! Dr. Gray informs me that he has 

 seen a second hybrid of the same parentage similarly striped. 



From these facts we see that the crossing of the several equine 

 species tends in a marked manner to cause stripes to appear on 

 various parts of the body, especially on the legs. As we do nut 

 know whether the parent-form of the genus was striped, the appear- 

 ance of the stripes can only hypothetically be attributed to reversion. 

 But most persons, after considering the many undoubted cases of 

 variously coloured marks reappearing by reversion in my experi- 

 ments on crossed pigeons and fowls, will come to the same conclu- 

 sion with respect to the horse-genus; and if so, we must admit 

 that the progenitor of the group was striped on the legs, shoulders, 

 lace, and probably over the whole body, like a zebra. 



Lastly, Professor Jaeger has given 39 a good case with pigs. He 



35 ' Philosoph. Transact.,' 1821, p. these, as with the horse and ass. are 



20. sometimes double: see Mr. Blyth. in 



3S Solater, in ' Proc. Zoolog. Soc.,' the paper just quoted, and in ' Indian 



1862, p. 163: this species is the Sporting Keview,' 1856, p. 3_'0 : and 



Ghor-Khur of N.W. India, and has Col. Hamilton Smith, in 'Nat. Library, 



often been called the Hemionus of Horses,' p. 318; and 'Diet. Class. 



Pallas. See, also, Mr. Myth's ex- d'Hist. Nat.,' torn. iii. p. 563. 



cellent paper in ' Journal of Asiatic 38 Figured in the ' Gleanings from 



Soc. of Bengal,' vol. xxviii., 1860, p. the Knowsley Menageries,' by Dr. J. 



229. E. Gray. 



37 Another species of wild ass, the 39 ' Darwin'sche Theorie und ilni 



true E. hemionus or Kiang, which Stellung zu Moral UDd Leligion,' p 



ordinarily has no shoulder-stripes, is 85. 

 said occasionally to have them ; and 



VOL. II. C 



