PROTECTIVE RESEMBLANCE IN ANIMALS. 175 



CHAPTER XYII. 



PROTECTIVE RESEMBLANCE IN ANIMALS. 



THAT the colours of animals tend to assimilate themselves 

 to the natural surroundings of the animals themselves is 

 a fact which has long been known in natural history ; and 

 it is, indeed, one which is self-apparent to every sportsman 

 and to every traveller in the wilder regions of the globe. 

 For instance, everyone is probably aware that desert- 

 haunting animals, like lions, gazelles, wild asses, jerboas, 

 and many species of birds, generally have a uniform 

 sandy- coloured coat, which renders them at a short distance 

 almost or completely invisible in their native wastes. 

 Then, again, every English sportsman knows how com- 

 pletely the coloration of the partridge and the hare assimi- 

 lates with that of the stubble or ploughed fields in which 

 they are wont to lie ; while the mottled blacks and browns 

 of the woodcock and snipe accord so exactly with the hues 

 of decaying leaves and grass that the inexperienced eye 

 will often fail to detect a wounded bird even when lying 

 close to the feet, and scarcely anyone can distinguish 

 the living birds when on the ground. The brilliant 

 vertical orange and black stripes of the tiger and zebra, 

 when seen in a menagerie or a museum, do not strike us as 

 resembling anything in inanimate nature. In its native 

 jungle, largely composed of upright yellow stems of tall 

 grasses, between which are narrow intervals of deep black 

 shade, the colour of the tiger is, however, admirably 

 suited to its surroundings ; and it is stated that the stripes 

 of the zebra are arranged in such proportions as exactly to 

 match the pale hue of arid ground by moonlight, so that 

 on such occasions these animals are alsolutely invisible 

 even at very short distances, while they are by 110 means 

 easy to distinguish at a moderate distance even in broad 

 daylight. We hardly need refer to the white colour of 

 polar animals, such as bears, ermines, foxes, hares, &c., 



