326 FISHES. [Chap. X. 



the eastern coast of the island, where it attains a 

 length of from twelve to fifteen feet, including the ser- 

 rated rostrum from which its name is derived. This 



HEAD OP THE SAW-FiSH (PRISTIS ANTIQUOEUM). 



powerful weapon seems designed to compensate for the 

 inadequacy of the ordinary maxillary teeth which are 

 unusually small, obtuse, and insufficient to capture and 

 kill the animals which form the food of this predatory 

 shark. To remedy this, the fore part of the head and 

 its cartilages are prolonged into a flattened plate, the 

 length of which is nearly equal to one third of the 

 whole body; its edges being armed with formidable 

 teeth, that are never shed or renewed, but increase in 

 size with the growth of the creature. 



The Rays form a large tribe of cartilaginous fishes 

 in which, although the skeleton is not osseous, the de- 

 veiopment of organs is so advanced that they would 

 appear to be the highest of the class, approaching nearest 

 to amphibians. They are easily distinguished from the 

 sharks by their broad and flat body, the pectoral fins 

 being expanded like wings on each side of the trunk. 

 They are all inhabitants of the ocean, and some grow 

 to a prodigious size. Specimens have been caught of 

 twenty feet in breadth. These, however, are of rare 



