122 TELKGONY AND UETERSION. 



have been derived from remote ancestors." * Reversion 

 lias, many think, been proved to occur in pigeons, and it is 

 said to be very probable in the liorse family. In Chile, 

 horses living under conditions not unlike those enjoyed by 

 their ancestors in Andalusia, are said to have remained 

 unaltered ; whereas in the eastern parts of South America 

 the horses some years ago were chiefly dun-coloured with 

 large coarse heads. Darwin thought this difference might 

 also be due to reversion.! Mr. T. D. A. Cockerell recently 

 pointed out that "in New Mexico one frequently sees small, 

 usually pale yellowish-brown horses, with extremely well- 

 marked leg stripes." He believes the small horses "are 

 descendants of the horses which ran wild in former years 

 over New Mexico," and that there can be little doubt "that 

 they represent an atavistic variety." J 



But hybrids between members of the horse family afford 

 still stronger evidence of reversion. Lord Morton's quagga 

 hybrid, though but faintly striped on the body, had distinct 

 transverse bars on the legs, i. e. stripes which were neither 

 present in the dam nor in the quagga sire ; and many mules 

 have often leg stripes, and occasionally shoulder stripes in 

 addition to a dorsal band. Some mouths ago I saw in 

 the South of France a light-coloured mule with the legs 

 striped as distinctly as in the ass of Soraaliland. Fre- 

 quently, though there are numerous stripes on the mule, 

 neither the sire nor dam has either leg or face stripes. 

 I have already described at some length the plan of the 

 stripes in my yearling hybrid. From this description it 

 appears that Romulus differs in a most pronounced manner 

 in the number and arrangement of his stripes, not only 

 from his sire but from all the varieties of the Burchell 

 group of zebras. But if one may judge from the markings 

 on the Norwegian with the striped face, Romulus also 



* ' Tiie Germ.plasm,' p. 316. 



f 'Animals and Plants,' vol. i, p. 54; vol. ii, p. 6. 

 + Nutui-e, March lltli, 1S97, p. -139. lam indebted to Mr. Cockerell for 

 a photograph showing the leg stripes in one of these New Mexican ponies. 



