SAW-FISHES. 



107 



are then seized by them and swallowed. They feed also largely on 

 cuttle-fishes. 



Fig-. 95. 



/& 



Lower view of head of Saw-fish. 



The Rldnobatidce (Case 42) contain the genera Rhynchobatus, [Case 42.] 

 Rhinobatus, and Trygonorhina. Preparations of their curious den- 

 tition are exhibited in Table-case C. They feed on hard-shelled 

 animals, and attain scarcely a length of 8 feet. They are confined 

 to the coasts of tropical and subtropical seas. 



The Torpedinidce, or Electric Rays (Case 42). — The electric 

 organs with which these fishes are armed are large, flat bodies, 

 lying one on each side of the head ; they consist of an assemblage 

 of vertical hexagonal prisms, whose ends are in contact with 

 the integuments above and below. The fish gives the electric 



