150 



ZOOLOGY. 



with a long, erect spine or " sting." Some live in fresh 

 water. 



The devil-fish {Ceplialopterus diabolus) of the coast of 

 South Carolina and Florida is the largest of our rays, being 

 eighteen feet across from tip to tip of its pectoral fins, and 

 ten feet in length, weighing several tons. It sometimes 

 seizes the anchors of small vessels by means of the curved 

 processes of its head and swims rapidly out to sea, carrying 



Fig. 192. — Chimcera vulgaris. From Liitken's Zoology. 



the craft along with it. Closely allied to our devil-fish is 

 the Ceratoptera (Fig. 19 L). 



Order 2. HolocephalL — This small but interesting group 

 of sharks is represented by the ChimcBra (Fig. 192) of the 

 North Atlantic, and CaUorliynclms of the antarctic seas. 

 In these fishes the four gill-ojjenings are covered by a 

 membrane, thus approaching the true bony fishes; there 

 are but four teeth in the upper and two in the lower jaw. 



Sub-Class II. — Gaxoidei {Garpikes, Lung-fishes). 



The term Ganoid was applied to these fishes from the 

 form of the scales, which in most of the species are angular, 

 square, or rhomboidal, and covered with enamel, as seen in 



