ACANTHOPTERYGII. 179 



HemirampJius (Cuv.). Half -leak. As Belone, 

 but the lower jaw alone is prolonged into a beak. 



H. Europseus. Fig. 277 ; n. s. 



Order IV. ACANTHOPTEEYGII. 



Jaws free ; gills comb-like ; gill-covers and ori- 

 fices generally large ; first rays of the dorsal, pec- 

 torals, and anal, and generally the first ray of each 

 ventral, unjointed, inflexible, and spinous. 



Ventrals behind the pectorals : 



Jaws forming a tube Fistulariada. 



Lips thick, fleshy. 



One dorsal Labrida. 



Two dorsals . Mugilidae. 



Ventrals before the pectorals : 



Wrist-joint of pectorals exterior Lophiadce. 

 Bays of dorsal flexible .... Gobiada. 

 Body thin, ribbon-like .... Cepoladte. 



Ventrals generally below the pectorals :* 



Rays of dorsal always exposed . Scombrida. 

 Rays of dorsal clothed with scales Ckatodontida. 

 Spinous rays of dorsal falling into 



a groove. 



Gill-covers unarmed .... Sparidtf. 

 Gill-covers toothed. 



Head covered with bony 



plates Triglada. 



Head not plated. 



No teeth on the palate . Sci&nada. 

 Teeth on the palate . . Percadte. 



* In Gasterosteus they are behind, and in Cottus and Trachinus, 

 before the pectorals. 



N2 



