956 : _ FISHES—PERCIDA. 
128. Roccus 1IntERRUPTUS (Gill) J. & G. 
Wellow Bass. 
Labrax chrysops, GIRARD, Pac. R. R., Expl., x, 1858, 29. (Not Perca chrysops of Rafinesque.) 
Morone interrupta, GILL, Proc. Acad. Nat. Sci. Phila., 1860, 48.—JORDAN, Man. Vert., 
1876.—GILL, Ich. Capt. Simpson’s Report, 1876; JORDAN, Man. Vert., 2d Ed., 1878, 232. 
Roccus interruptus, JORDAN and GILBERT, Synopsis Fish N. A. 
Description.—Brassy, tinged with olivaceous above; sides with 7 very distinct longi- 
tudinal black bands, darker than in the other species, those below the lateral line in- 
terrupted posteriorly, the posterior part alternating with the anterior; body oblong- 
ovate, with the dorsal outline much arched; head depressed, somewhat pointed, its. 
profile concave; eyes large, their diameter equaling length of snout; mouth somewhat 
oblique, maxillary nearly reaching middle of orbit; spines very robust, second anal 
Spine 2-5 length of head; dorsal fins little connected; head 3 in length; depth 23; D. 
IX-I, 12; A. III, 9; Lat. 1. 50. 
Habitat, Lower Mississippi Valley, extending up the Ohio to the mouth of the 
Wabash or beyond. It does not seem to be very common anywhere except in the Lower 
Misissippi, and nothing special is known of its habits, which probably differ little from 
those of the White Bass. 
Diagnosis.—The Yellow Bass may be known from the White Bass by 
the fact that the two dorsal fins are connected by a low membrane. The 
color in life is yellow, not silvery, and the black lateral stripes are very 
conspicuous. 
\ 
INE IEI YC OO IEIES IO Id eg UID) adi, Ah Jab l) IP Ie) lal las) 
Body more or less elongate, terete or compressed, covered more or less completely with 
rather small, ctenoid, adherent scales; lateral line usually present, not extending on the 
caudal fin; mouth terminal or inferior, small or large, the premaxillaries protractile or 
not; maxillaries large or small, without distinct supplemental bone; jaws, vomer, and 
palatines with bands of teeth, which are usually villiform, but sometimes mixed with 
canines, occasionally the teeth on the vomer or palatine are absent; head naked or more 
or less scaly ; preopercle entire or serrate; opercles usually ending in a flat spine; bran- 
chiostegals 6 or 7; gills 4, a slit behind the fourth; gill-membranes free or connected, 
not joined to the isthmus; gill-rakers, slender, toothed; pseudobranchiz smali or 
granular and concealed, or altogether wanting ; lower pharyngeals separate, with sharp 
teeth; fins generally large; two dorsals, the first of 6 to 15 spines; anal fin with one or 
two spines (three in Percichthys, a fresh water genus from Chili.) Ventrals thoracic, I, 
5; pectorals often very large; caudal lunate, truncate or rounded; anal papilla often 
present; air-bladder small and adherent, often entirely wanting; pyloric ceca few; 
vertebree 30 to 45; genera about 20; species 90 to 100; inhabitants of the fresh waters 
of cool regions, most of them being American, and nearly all belonging to the fauna of 
the United States. The great majority of the species belong to the sub-family of 
Etheostomatine, the Darters, all the species of which group are American. They are 
