Odd Fish 171 



waters of such harbour fish with the eyes 

 completely hidden beneath their skin. 

 Nature, however, attempts to compen- 

 sate all blind creatures by greatly aug- 

 menting certain other senses, and in 

 these animals a number of papillae, 

 which are situated on the head are ex- 

 tremely sensitive organs that serve to 

 help the fish in probing the darkness. 

 It has been ascertained in the case of 

 blind cave fish, that it is only in the 

 adult that the fish is sightless, being in 

 infancy provided with a quite serviceable 

 pair of eyes. 



Every portion of a fish's anatomy is 

 open to enormous modification to meet 

 the exigencies of environment. This 

 applies to the eyes as much as to any 

 other organ. A small fresh- water fish 

 inhabiting the rivers of tropical America, 

 the so-called four-eyed fish, has each of 

 its very prominent eyes divided into two 

 portions, the upper half being for use 



