PISCES. 307 



1. PERCA. Body oblong, somewhat compressed: 

 ventrals beneath the pectorals : branchiostegous membrane 

 with seven rays : preopercle with the basal and posterior 

 margins denticulated : jaws, vonier, and palatines, all armed 

 with small teeth : scales rough ; not easily detached. 



(1. PERCA.) Two dorsals : opercle with the upper half covered -with 

 scales, terminating ibehind in a flattened point : infra-orbitals 

 slightly denticulated: tongue smooth. 



(2. LABRAX.) Two dorsals: opercle entirely covered with scales, 

 terminating behind in two spines : infra-orbitals not denticu- 

 lated: tongue rough with minute teeth. 



(3. SERRANUS.) A single dorsal: cheeks and opercle covered with 

 scales ; the latter terminating behind in one or more flattened 

 points: jaws with some elongated sharp teeth among the smaller 

 ones. 



(4. ACERINA.) A single dorsal: head without scales, pitted with 

 indentations : opercle terminating behind in a single spine : 

 teeth uniform. 



2. TRACHINUS Head compressed ; body elongated : 



ventrals before the pectorals : two dorsals ; the first short ; 

 the second, as well as the anal, long : branchiostegous mem- 

 brane with six rays : opercle with one strong spine directed 

 backwards : two small spines in front of the eye : both 

 jaws, as well as the vomer and palatines, armed with 

 minute teeth. 



(1.) SPHYRJENA. Body elongated: two dorsals remote from each 

 other : head oblong : lower jaw pointed, longer than the upper, with 

 some of the teeth larger than the others: branchiostegous membrane 

 with seven rays: no denticulations on the preopercle, or spines on the 

 opercle. 



3. MULLUS Body oblong, thick: ventrals a little 



behind the pectorals : two dorsals widely separated : branch- 

 iostegous membrane with four rays : no denticulations on 

 the preopercle, or spines on the opercle : teeth in the 

 lower jaw and on the palatines only : chin with two long 

 barbules: scales large, deciduous*. 



* Obs. The characters of this and the last genus depart rather from those of the rest of the 

 Percidce. With respect to the Mullets, Cuvier observes that they might almost be considered as 

 a distinct family. 



U2 



