58 HOESES. Chap. II 



however unlike in size and appearance, and several of those 

 in India and the Malay archipelago, present a similar range 

 and diversity of colour. The English race-horse, however, 

 is said 30 never to be dun-coloured ; but as dun and cream- 

 coloured horses are considered by the Arabs as worthless, 

 " and fit only for Jews to ride," 31 these tints may have been 

 removed by long-continued selection. Horses of every colour, 

 and of such widely different kinds as dray-horses, cobs, and 

 ponies, are all occasionally dappled, 32 in the same manner as 

 is so conspicuous with grey horses. This fact does not throw 

 any clear light on the colouring of the aboriginal horse, but 

 is a case of analogous variation, for even asses are sometimes 

 dappled, and I have seen, in the British Museum, a hybrid 

 from the ass and zebra dappled on its hinder quarters. By 

 the expression analogous variation (and it is one that I 

 shall often have occasion to use) I mean a variation occurring 

 in a species or variety which resembles a normal character in 

 another and distinct species or variety. Analogous variations 

 may arise, as will be explained in a future chapter, from two 

 or more forms with a similar constitution having been ex- 

 posed to similar conditions,— or from one of two forms having 

 reacquired through reversion a character inherited by the 

 other form from their common progenitor, — or from both 

 forms having reverted to the same ancestral character. We 

 shall immediately see that horses occasionally exhibit a ten- 

 dency to become striped over a large part of their bodies ; 

 and as we know that in the varieties of the domestic cat and 

 in several feline species stripes readily pass into spots and 

 cloudy marks — even the cubs of the uniformly-coloured lion 

 being spotted with dark marks on a lighter ground — we 

 may suspect that the dappling of the horse, which has been 



30 'The Field,' July 13th, 1861, p. because it has been stated (Martin, 

 4'2. 'History of the Horse,' p. 134) that 



31 E. Vernon Harcourt, ' Sporting duns are never dappled. Martin (p. 

 in Algeria,' p. 26. 205) refers to dappled asses. In the 



32 I state this from my own obser- Farrier ' (London, 1828, pp. 453, 455) 

 vations made during several years on there are some goo J remarks on thj 

 the colours of horses. I have seen dappling of horses ; and likewise in 

 cream-coloured, light-dun and mouse- Col. Hamilton Smith on 'The Horse.' 

 dun horses dappled, which I mention 



