30 NEW-YORK FAUNA. 



THE OBSCURE FRESH-WATER BASS. 



Centrarchus obsccrus. 

 PLATE XVII. FIG. 48. -= (CABINET OF THE LYCEUM.) 



Characteristic. Body not gibbous. 



Description. Body compressed, regularly arched above, not gibbous, highest along the 

 spinous portion of the dorsal fin. Scales small, orbicular, concentrically striate on their free 

 surfaces, covering the head and body, and rising very slightly on the base of the dorsal. 

 Lateral line tubular above the upper margin of the opercle ; makes a curve downwards over 

 the point of the opercle, then rises a little anterior to the first spinous ray of the dorsal, and 

 then becomes concurrent with the line of the back. Head moderately small, and somewhat 

 pointed ; sloping gradually to the nape, thence ascending more rapidly to the dorsal ray. 

 Eyes very large. Nostrils double, distant, the posterior largest ; a small mucous pore be- 

 neath the anterior nostril. Lower jaw longest. Numerous fine teeth in both jaws, very acute, 

 and recurved ; forming many rows in front, and fewer on the sides of the jaw. Still more 

 minute teeth on the vomer and palatines. Opercular bones scaly ; the opercle with a membra- 

 nous margin, and terminating in a flat point, which is occasionally double. 



The dorsal fin arises behind the base of the pectorals, composed of nine spinous and thirteen 

 simple rays. The first spinous is shortest ; the first of the soft portion simple ; the remainder 

 articulated, and much higher than the spinous portion : it is coterminal with the anal fin. 

 Pectorals oblong, and composed of sixteen rays ; the upper ray subspinous, simple. Ventral 

 fin pointed, contiguous, composed of one spinous and five branched rays. Anal rounded, of 

 three spinous and twelve branched rays ; the first spine short, the others gradually longer. 

 Caudal fin emarginate, of seventeen entire and three accessory rays on each side. All the 

 rays of this fin are broad and compressed, with scales ascending high up towards their extre- 

 mities. 



Color. A general greenish-brown or dark-olive, with faint metallic bronze on the upper 

 parts ; beneath lighter. 



Length, 6-0- 8-0. 



Fins, D. 9.1.12; P. 16; V, 1.5; A. 3.12; C. 17 f 



This species, which I do not find exactly described, was obtained from Onondaga creek, 

 where it is called, with many others, Black Bass. The Cichla minima of Lesueur may pos- 

 sibly prove to be the young of this species. 



(EXTRA-LIMITAL.) 



C. pentacanthus. (Cuv. et Val. Vol. 3, p. 88.) Dorsal fin with ten, and anal with five spines. Five 

 inches. River Wabash. 



