PROTECTIVE RESEMBLANCES AMONG ANIMALS 37 



Importance of Concealment as Influencing 



Concealment, more or less complete, is useful to many 

 animals, and absolutely essential to some. Those which have 

 numerous enemies from which they cannot escape by rapidity 

 of motion find safety in concealment. Those which prey 

 upon others must also be so constituted as not to alarm them 

 by their presence or their approach, or they would soon die 

 of hunger. Now it is remarkable in how many cases nature 

 gives this boon to the animal, by colouring it with such tints 

 as may best serve to enable it to escape from its enemies or 

 to entrap its prey. Desert animals as a rule are desert- 

 coloured. The lion is a typical example of this, and must be 

 almost invisible when crouched upon the sand or among 

 desert rocks and stones. Antelopes are all more or less 

 sandy -coloured. The camel is pre-eminently so. The 

 Egyptian cat and the Pampas cat are sandy or earth-coloured. 

 The Australian kangaroos are of the same tints, and the 

 original colour of the wild horse is supposed to have been a 

 sandy or clay-colour. 



The desert birds are still more remarkably protected by 

 their assimilative hues. The stonechats, the larks, the quails, 

 the goatsuckers and the grouse, which abound in the North 

 African and Asiatic deserts, are all tinted and mottled so as 

 to resemble with wonderful accuracy the average colour and 

 aspect of the soil in the district they inhabit. The Rev. H. 

 Tristram, in his account of the ornithology of North Africa 

 in the first volume of the Ibis, says : "In the desert, where 

 neither trees, brushwood, nor even undulation of the surface 

 afford the slightest protection to its foes, a modification of 

 colour which shall be assimilated to that of the surrounding 

 country is absolutely necessary. Hence without exception the 

 upper plumage of every bird, whether lark, chat, sylvain, or 

 sand-grouse, and also the fur of all the smaller mammals, and 

 the skin of all the snakes and lizards, is of one uniform isabelline 

 or sand colour." After the testimony of so able an observer 

 it is unnecessary to adduce further examples of the protective 

 colours of desert animals. 



Almost equally striking are the cases of arctic animals 

 possessing the white colour that best conceals them upon 



