318 PHILOSOPHY OF ZOOLOGY. 



nary size. Having by a leap raised themselves above the 

 surface of the water, they continue in the air and move for- 

 wards, seldom farther than a hundred yards, by the action 

 of their pectoral fins. The continuance of their flight is in- 

 terrupted by the drying of the membrane of these fins, 

 when they again fall into the water. 



There is one species of fish fPerca scandens of LIN. 

 Trans, vol. iii. p. 62.), which appears capable of climbing. 

 By this motion, according to Lieutenant DAI^DORF* of 

 Tranquebar, it sometimes raises itself five feet above the sur- 

 face of the water, mounting up the crevices of trees. The 

 spines of its gill-cover retain it in its position ; and when 

 the body is bent to one side, the spines of the anal fin fix 

 themselves in the bark ; and when the body is then brought 

 back to its ordinary shape, the head has reached a higher 

 elevation. The spines of the expanded gill-covers again 

 keep a firm hold, and a similar twisting of the body takes 

 place in another direction. The spines of the dorsal fin 

 contribute likewise to this extraordinary progression. The 

 flying-fish leave the water to escape from other fishes which 

 prey upon them ; but the object to be gained by these 

 movements of this fish has not been ascertained, nor has 

 even a conjecture been offered on the subject. 



A few fishes possess an organ of adhesion, which is 

 generally termed a Sucker. In some of these it is si- 

 tuate on the upper part of the head, while in others it is 

 placed on the thorax. In the celebrated fish called the Re- 

 mora, it is coronal, of an oval form, and consisting of trans- 

 verse rows of cartilaginous plates, connected by one edge to 

 the surface of the head, while tke other edge is free, and 

 finely pectinated. A longitudinal partition divides the plates 

 in the middle of the head. In the spaces between the plates, 

 and on each side of the partition, a row of fleshy tubercles 



