482 FISHES. 



Of "Flying Gurnards" three species only are known, 

 which are very abundant in the Mediterranean, the tropical 

 Atlantic, and Indo-Pacific. They, and the Flying Herrings 

 (Exocoetus), are the only fishes which are enabled by their 

 long pectoral fins to take flying leaps out of the water, and 

 deserve the name of " Flying-Fishes." They are much heavier, 

 and attain to a larger size, than the Exocoeti, specimens of 

 eighteen inches in length not being scarce. When young, 

 their pectorals are much shorter, and, consequently, they are 

 unable to raise themselves out of the water {Ceiplialacanthus). 

 The vertebral column shows a singular coalescence of the 

 anterior vertebrse, which form a simple tube, as in Fistulcwia. 



We iasert here as an appendix to this division the small 

 family of Pegasidcc, the natural affinities of which are not yet 

 clearly understood, but which resembles in some of its char- 

 acters the Cataphracti. 



Fifteenth Family — Pegasid^e. 



Body entirely covered luith hony plates, ancliylosed on the 

 trunk and movahle on the tail. Barhds none. The margin of 

 the vpper jaw is formed ly the intermaxillaries and their cuta- 

 neous proloiigation, which extends downwards to the extremity 

 of the maxillaries. Gill-cover formed ly a large plate, homolo- 

 gous to tJie operculum, prwoperculum, and suboperculum ; hi- 

 teroperculum a long fine hone, hidden helow the gill-plate. One 

 rudimentary iranchiostegal. The gill-plate is united ivith tlie 

 isthmus hy a narrow membrane ; gill-openings narrow, in front 

 of the base of the pectoral fin. Gills four, lamcllated. Pscudo- 

 Iranchim and air-bladder absent. One short dorsal and anal 

 fin, opposite to each other. Ventral fin present. Ovarian sacs 

 closed. 



One genus only is known, Pegasus. Its pectoral fins are 

 broad, horizontal, long, composed of simple rays, some of wliich 



