958 FISHES—PERCIDZA. 
g. Gill-membranes more or less broadly united; belly with ordinary scales. 
h. Lateral line complete; maxillary adnate to the preorbital. 
DIPLESIUM,. 
gg. Gill-membranes scarcely united ; anal as large as second dorsal. 
4. Belly, with enlarged caducous plates. : : COTTOGASTER, 
ii. Belly without enlarged plates, anteriorly naked, posteriorly scaled 
like the sides. : : 6 : : ; , IMOSTOMA. 
cc. Premaxillaries not protractile. 
j. Lateral line complete. 
k. Ventral line with a series of enlarged, spinous, caducous scales, 
or if these are fallen, a naked strip. 
1. Mouth smail, inferior, beneath a pig-like snout. . . PERCINA. 
WW. Mouth larger, the snout not projecting beyond it. 
ALVORDIUS. 
kk. Ventral line without caducous scales, 
m, Gill-membranes scarcely connected. j : NOTHONOTUS. 
mm. Gill-membranes broadly connected. : ‘ NANOSTOMA. 
jj. Lateral line present, incomplete. 
m, Gill-membranes broadly united. . : : ETHEOSTOMA. 
nn, Gill-membranes separate, or nearly so, . . PdacILICHTHYS. 
. jj. Lateral line obsolete. : : : 6 -  MICROPERCA. 
GENUS 69. PERCA. Linnzeus. 
Perca, LINNZUS, Systema nature. Ed. x., 1858. 
Type, Perca fluviatilis L. 
Etymology, Latin, Perca, a perch; Greek, perche, from perchos, dusky. 
Body elongate, fusiform, somewhat compressed; head conical; its sides mostly scaly ; 
the operculum chiefly naked and rough-striate, armed with a single spine ; preoperculum 
scapular and caracoid bones serrated; mouth moderate; teeth all in villiform bands; 
dorsal fins not connected, the first with about thirteen spines; anal with two slender 
spines; caudal forked; scales small, rough; lateral line complete; pyloric ceca 3; ver- 
tebra 21-20. 
129. PrRCOA AMERICANA Schranck. 
Wellow Perch; Rimged Perch; Common Perch. 
Perca americana, SCHRANCK, 17, fide Gill.—JORDAN and GILBERT, Klippart’s Report Fish 
Comumr. Ohio, 1877, 65.— JORDAN, Man. Vert., 2d Ed., 1878. 
Perca fluviatilis, var. americana, STEINDACHNER, Butrage, 1877. 
Bodianus flavescens, MITCHILL, Ph. Trans, N. Y., 1815, i, 421. 
Centropomus luteus, RAFINESQUE, Precis des Dicouvertes Somiologiques, 1814, 19. 
Perca flavescens, CUviER, Regne Animal, 1817.—Cuv. and VAL., Hist. Nat. des Poissons, 
ii, 1828, 46.—RicHarpDson, Fauna Bor'-Amer., Fishes, 1836, 74.—DEKAyY, Nat. Hist. 
N. Y., Fishes, 1842, 3—SroreR, Synopsis, 1846, 17.—KirRTLAND, Bost. Journ. Nat. 
Hist., v, 1847, 337.—AGassiz, Lake Superior, 1850, 291.—GUNTHER, Cat. Fishes, Brit. 
Mus., i, 59, 1859.—HoLBROOK, Ich. 8. Car., 1860.—SToRER, Hist. Fishes Mass., 1867.— 
JORDAN, Man. Vert., 1876, and of authors generally. 
