LOCOMOTION OF FISHES. 



105 



rudimentary, or very small. In the Cotti^ or bull- 

 beads, it becomes very much developed at the tip. 



and becomes broadened by a wide and thin mem- 

 brane intervening between the rays. In Trigla^ 

 or the gurnards, it continues the broadened form 

 and wide membrane, but adds length to its breadth ; 

 in Trigla fasciata^ Schneider, it is more than half 

 the length of the fish. In some of our native species 

 it is of great expanse, and, in addition, is adorned 

 with the brightest and most brilliant colours. In 

 another curious tribe of fishes it is singular and 

 scarcely less developed ; in the Pegasus draconis it 

 appears like two little fans extended from the side, 

 as if the fish were about to fly. In a foreign species, 

 gurnard, which we shall represent, the pectoral fins 

 are very beautiful. 



