88 A Guide to the Zoological Collections i?i the Fish Gallery. 



Characteristic Fishes of the Deep Sea. 



In Cases 15-20 are exhibited specimens of some fishes 

 that are specially adapted for life under the peculiar 

 conditions that prevail in the depths of the sea. 



In Case 15 are specimens of fishes that, in all pro- 

 bability, live in constant darkness or gloom. The eyes 

 show marked degeneration, but, so far as is known, 

 there is no compensating overgrowth of any of the other 

 organs of sense. 



In Case 16 are specimens of fishes that undoubtedly 

 live at the bottom, in depths to which no daylight 

 penetrates. The eyes are completely-hidden rudiments, 

 but, so far as is known, there is no compensating over- 

 growth of any of the other organs of sense. 



In Case 17 are specimens of fishes that live in dark- 

 ness and have very degenerate eyes, but have the sense 

 of touch greatly developed in compensation. 



In Case 18 are specimens of fishes that undoubtedly 

 live at depths to which little, if any, daylight reaches. 

 Their eyes are of enormous size to catch such light — 

 whether faint gleams of daylight or phosphorescent 

 light — as does exist. 



In Case 19 are specimens of fishes that live in con- 

 stant darkness or gloom, but possess their own indepen- 

 dent means of illumination. 



In Case 20 are specimens that illustrate in an extreme 

 degree the extraordinary rapacity and voracity of certain 

 deep-sea fishes. 



