The first portion of the dorsal fin, or the entire first dorsal when two are present, with simple spinous rays: also the anal and ventrals with one or more of the anterior rays generally spinous.
Scales generally rough, with ciliated margins: margin of the opercle or pre-opercle, sometimes both, denticulated, or armed with spines: both jaws, as well as the vomer, and almost always the palatine bones also, armed with teeth.
Body oblong, somewhat compressed: ventrals beneath the pectorals: branchiostegous membrane with seven rays: preopercle with the basal and posterior margins denticulated: jaws, vomer, 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 behind 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 denticulated: 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.
Head compressed; body elongated: ventrals before the pectorals: two dorsals; the first short; the second, as well as the anal, long: branchiostegous membrane 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.
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.
Body oblong, thick: ventrals a little behind the pectorals: two dorsals widely separated: branchiostegous 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.
Infra-orbitals extending more or less over the cheeks, articulating behind with the preopercle: head mailed, or otherwise armed.
Head mailed; in the form of a parallelopiped: opercle, and bones of the shoulder, armed with spines: body scaly: two dorsals: three detached rays beneath the pectorals: branchiostegous membrane with seven rays: fine velvet-like teeth* in both jaws and on the front of the vomer.
Head broad, depressed; more or less armed with spines: body naked, without scales: two dorsals, distinct, or very slightly connected: lower rays of the pectorals simple: branchiostegous membrane with six rays: teeth in both jaws, and also on the front of the vomer; none on the palatines: ventrals small.
Head broad, depressed; armed with spines and tubercles: body attenuated behind, mailed with angular plates: two dorsals, nearly contiguous: branchiostegous membrane with six rays; furnished, as well as the chin, with small thread-like filaments: teeth in both jaws; none on the vomer or palatines: ventrals small† .
Head compressed, armed more or less with spines and tubercles: body oblong, scaly: a single dorsal: lower rays of the pectorals simple: branchiostegous membrane with seven rays: velvet-like teeth in both jaws, and on the palatines.
(1. Sebastes). Head scaly; spines on the preopercle and opercle; no tubercles.
Head without spines or tubercles: body generally more or less protected by shield-like plates: several free spines instead of a first dorsal: ventrals reduced nearly to a single spine: branch-iostegous membrane with three rays: teeth in both jaws; none on the vomer or palatines.
* The terms employed to designate the different forms of teeth in fishes have been, in most instances, adopted from Cuvier. See Hist. Nat. des Poiss. torn. i. p. 362. See also Yarrell's British Fishes, vol. i. p. 99.
† Since the publication of my Catalogue, I have inclined to the opinion that this group should rank higher than as a mere subdivision of the genus Coitus.
(1. Gasterosteus). Bones of the pelvis united, forming a triangular plate on the abdomen: ventrals with only one soft ray.
(2. Spinachia). Bones of the pelvis separate: ventrals with two soft rays: lateral line armed with large carinated scales.
Preopercle denticulated; opercle with spines: mouth but little protractile: no teeth on the vomer or palatines: bones of the face and cranium often cavernous, causing the snout to appear more or less protuberant.
Head protuberant, covered entirely, as well as the body, with scales: two dorsals; the second much longer than the first: anal short: preopercle, except in advanced age, denticulated; opercle terminating behind in two flat spines: branchiostegous membrane with seven rays.
(1. Sclena). A row of strong pointed teeth in each jaw, accompanied, in the upper, by smaller ones behind: anal with only one small spine: no cirrus on the chin.
(Umbrina). A broad band of fine small teeth in each jaw without an anterior row of stronger ones: anal with two spines, the second strong: a barbule beneath the symphysis of the lower jaw.