NATURAL SCIENCES OF PHILADELPHIA. 221 



Baird and Dr. Stimpson at Beesley's Point, and by the latter and the author 

 at Beaufort, North Carolina, the present article is submitted. 



EUCHALARODUS,* Gill. 



Body oblong, ovate-rhombic, with the caudal peduncle moderate and uni- 

 form. 



Scales minute, distant, immersed, each one on the colored side with several 

 slender teeth behind directed outwards; on the light side smooth or uniciliate. 



Lateral line straight, simple, continuous through a series of short tubes, 

 channelled along their posterior half. 



Head moderate, rhombic, depressed above the eye, with the snout nearly 

 rectilinear and the rostral area rhombic ; covered with minute scattered scales 

 extending along the interorbital area, and with an osseous ridge below the up- 

 per eye, and continued from its hinder angle backwards, where it is expanded, 

 and separated from an oblique bony tubercule on the scapula. Eyes moderate, 

 approximated, even, chiefly in the anterior third of the head. Nostrils of the 

 dark side even longitudinally, the anterior next to the border of the snout; 

 the posterior between orbits in front; of the left side, on the left side of the 

 ridge, approximated ; the hinder close in front of the dorsal fin at its inner 

 angle; anterior nostrils tabular and nearly blind, minutely perforated near the 

 end ; posterior transversely fissured, with lips. Opercula well developed. 



Mouth moderately small, with the cleft oblique (c. 45) in front of eye; the 

 jaws of the respective sides nearly equal ; the lower scarcely prominent, and 

 with a very obtuse, rounded chin. 



Lips moderate and simple; the latter attached by a froenum at the left side 

 of the symphisis. 



Tongue slender, but well developed and free. 



Teeth uniserial, in an imperfect row on the dark side, moderate, moveable, 

 reclining inwards, compressed, capitate or constricted near the apex, and with the 

 apex itself blunt and emarginate, especially towards the symphisis ; palate 

 smooth. 



Branchial apertures free below, closed above the operculum. 



Branchiostcgal rays seven, exceptionally six. 



Dorsal '.fin with its rays simple, in moderate number ; its origin above the 

 upper eye, rapidly increasing, and with its rays converging towards the poste- 

 rior third. 



Anal fin with its middle rays highest, but directed obliquely forwards, and 

 with no true spine in front. 



Caudal convex behind. 



Pectoral fins moderate, obliquely rounded behind. 



Ventral subbrachial, normally developed. 



The interior pharyngeal bones are united, oblong, triangular, with the sides 

 rectilinear ; the posterior margin broadly emarginate, (without sinus at the 

 junction) bent upwards and trenchant ; behind and beneath sloping forwards, 

 and with a wide trihedral enlargement expanded downwards below at the mid- 

 dle. The teeth are blunt, paved, and on all the upper surface, except the de- 

 flected posterior marginal area. The lower pharyngeals are oblique, the mid- 

 dle largest; the first and second with two rows of molar teeth ; the third with 

 one. 



The branchial arches are provided on their external surfaces with soft, com- 

 pressed, unarmed, subunguiform rakers, decreasing from the first to the 

 fourth, oblong on the first, very short on the fourth, which alone has rudimen- 

 tary rakers on the internal surface. 



Such is the combination of characters, which distinguishes thiB remarkable 



1864.] 



* F.i/, well J ^axafi;, loose ; iJou;, tooth. 



