Hunters and Hunted 



cases they may aptly be described as bulging, and the 

 reason for this is that the animals may lie in hiding quite 

 below the surface of the water, with the exception of 

 their bulging eyes and nostrils ; thus they are exceedingly 

 difficult to detect, but, at the same time, can see all that 

 goes on around them. 



A very cursory survey of the animal kingdom will 

 suffice to show that nearly every animal, whatever its 

 colour, is lighter below than on its back. The reason for 

 this is easy of explanation. A shadow is cast by the 

 animal's body ; so that, being lighter underneath, this 

 shadow, which would render the animal conspicuous, is 

 neutralised. No words could explain this colouring so 

 well as it is demonstrated by two models side by side in 

 the Natural History Museum of London. The models 

 consist of a pair of birds in a glass case with base, back 

 and sides of pale grey. The birds themselves are made 

 of the same material as the lining of the case and the 

 same colour. One bird is self-coloured, the other is white 

 underneath. Viewed from a distance and illuminated by 

 the light which enters the top of the case, the self-coloured 

 bird, by reason of the shadow underneath it, can easily 

 be distinguished from the background ; the other bird, 

 the one which is lighter beneath, can only be distinguished 

 from the background with the greatest difficulty. 



Some animals are practically self-coloured ; the lion is 

 one ; but the lion follows up his prey by crawling along 

 close to the ground, so that his under parts are hidden 

 from view. Other animals, and they are not many, are 

 lighter above than below. The queer little water boatman 

 has a light-coloured back and a dark-coloured abdomen, 

 yet he conforms to the general rule of colouring, for he 

 swims on his back and so his lighter parts are underneath. 



Recognition or identification marks are nearly as 

 common amongst the quadrupeds as amongst the birds. 

 Several deer, the wapati is one, have white patches on the 

 rump ; the rabbit is an example which everyone may see. 



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