202 



BRANCH VERTEBRATA. 

 FIG. 349. 



FIG. 350. 



Nbribdon, monoc'eros. Narwhal. ( T ib-) 



The Nanrlial (nar'whal), or unicorn, has one of its 

 upper canines developed into a straight, spirally-twisted 

 pole of ivory, seven to ten feet long.* 



The Common Porpoise frequents the mouths of rivers, 



often venturing some dis- 

 tance up stream in pursuit 

 of herring and other migra- 

 tory fish.f 



The Delphi n as delphis is 

 the dolphin J of Grecian 

 mythology. 



The Sperm-whale is 

 found in deep water in all tropical regions. It is distin- 

 guished by forty or fifty conical teeth in the lower jaw, 

 which fit into cavities in the upper ; and l>y a singu- 



* This formidable weapon has been forced through the sides of a whale- 

 ship. It can be used only as a means of defense or of plowing up the mud for 

 food, as the animal feeds mainly iipon soft shell-fish. 



t It frequently comes to the surface of the water to breathe, where it 

 tumbles and frisks abo\it, presenting an appearance which, with its puffing, has 

 given it the name of the Puffing Pig. 



t This is common to all seas, but should not be confounded with the Dol- 

 phin of sailors, which in dying displays all the colors of the rainbow the latter 

 being the coryphene (kor ife' ne), a true scaly fish. 



Plio cce' na com -inuii in. 

 Common Porpoise. ( 3 \..) 



