COLOUR. 



329 



for the first time that the opposite operation is quite 

 possible, viz., that an artist can paint a sohd object so 

 as to obliterate the shadows, and as a result to remove 

 all appearance of solidity. . . . Hence, with solidity 

 eliminated and with colour harmony between environment 

 and object, the latter appears to be but a part of the 

 former." As Prjevalsky's horse (p. 640), the tarpan (p. 

 648), and many horses in countries where artificial selection 



I'koto by] 



[G. A. EWART. 



Fig. 400. — Yellow dun Norwegian pony. 



as regards colour is not practised by breeders, are fighter 

 in colour under the belly than on the upper part of the 

 body (as in dark coloured donkeys, Fig. 397), it is reason- 

 able to suppose that the ancestors of the horse possessed 

 this form of protective coloration. 



Many horses have dark stripes or dark markings 

 which evidently have no connection with variation due to 

 domesticity or to artificial selection, because they are always 

 uniform in character, and are much more frequent in wild 

 (p. 640 et seq.) and semi-wdld horses, than in those which 



