BRANCH CHORD AT A; CLASS PISCES: THE FISHES 281 



rays in external appearance are the saw-fishes ( Pristis 

 pcctinatis), which belong to this group. The body is 

 elongate and shark-like, and has a long sa\v-like snout. 

 This sa\v, which in large individuals may reach a length 

 of six feet and a breadth of twelve inches, makes its 

 owner formidable among the small sardines and herring- 



FIG. 114. The common skate, Raja erinacea. (From Kingsley.) 



like fishes on which it feeds. The saw-fishes live in tropi- 

 cal rivers, descending to the sea. 



The bony fishes (Teleostomi). The bony or true fishes 

 are distinguished from the lampreys and sharks and rays 

 by having in general the skeleton bony, not cartilaginous, 

 the skull provided with membrane bones, and the eggs 

 small and many. In this group are included all the 

 fishes of our fresh- water lakes, ponds, and streams as well 

 as most of the marine forms. Fish life, being spent under 



