328 



SKIN, COLOUR, AND HAIR. 



bviit having lost its appearance of thickness, and when 

 seen against a background of colour and pattern similar 

 to its own, will be essentially indistinguishable at a 

 short distance." Professor Poulton (author of Colours of 

 Animals), in drawing attention to the importance of this 

 discovery, says : " We are led to believe that any small 



Photo by} [James Haves. 



Fig. 399. — Horizontal stripes on the legs of a horse. 



object is solid and possesses a definite shape, solely 

 because of the varying depth of shade on parts of its 

 surface more or less shielded from light. Thus an artist 

 can make an object on the fiat surface of his canvas 

 appear to stand out as a solid, because he paints the 

 shadows as they would be caused by the varying degree 

 of light on the surface of a solid. Mr. Thayer has shown 



