FAMILY CYPRINIDjE LEBIAS. 215 



L. caurinus. (Richardson, F. B. A. p. 304.) Moderately compressed. Scales orbicular ; seventy- 

 five on the lateral line, twenty-four in a vertical line. Caudal deeply forked. D. 10 ; A. 9. Length 

 12i inches. Columbia River. 



L. oregoncnsis. (Id. lb. p. 305.) Brownish grey; belly silvery white. More elongated than the 

 preceding; head longer. Length thirteen inches. Columbia River. 



Genus Pcf.cilia, Schneider. Body little elongated. Jaws flattened, protractile, and but slightly cleft, 



with a single row of very small teeth. Opercles large, five-rayed. Dorsal above the anal. 

 P. multilincata. (Lesueur, Ac. Sc. Vol. 2, pi. 1.) Compressed. Several longitudinal series of black 



spots. Dorsal small, longer than high. Caudal straight. D. 14; A. 9; C. 26. Length one and 



a half inches. Florida. 



GENUS LEBIAS. Cuvier. 

 With many of the characters of the preceding . Teeth denticulated. Branchial rays five. 



THE SHEEPSHEAD LEBIAS. 



Lebias ovinus. 



PLATE XXVII. FIG. 64. 



The Shecpshead Killifish, Esox ovinus. Mitchill, Lit. and Phil. Soc. Vol. 1, p. 441, pi. 4, fig. 7. 

 Cyprinodon ovinus. Valenciennes, apud Humboldt, Obs. Zool. Vol. 2. 



Characteristics. Elliptical, compressed, with transverse stripes or spots occasionally obsolete. 

 Extremity of the tail pellucid. 



Description. Body much compressed : its greatest depth equalling one-half of the length of 

 the body and tail. Scales large, subquadrate, longest in their vertical diameter, rounded and 

 entire on their free edges ; at their radical edge, straight, with parallel horizontal striae ; on the 

 summit of the head, a central scale, with its entire margin free. The scales extend over the 

 cheeks, form an imperfect sheath for the dorsal, and extend far up the caudal fin, giving that 

 pellucid appearance noted in the specific phrase. A large plate or bony scale above the base 

 of the pectoral fin. Lateral line scarcely obvious. The head slopes rapidly down from before 

 the dorsal fin, and is much flattened between the eyes, which are distant. Nostrils contiguous 

 to the orbit. A number of mucous pores about the head and beneath the jaws. Opercular 

 margin entire, rounded. Branchial rays five. Jaws protractile, with from sixteen to eighteen 

 tricuspid teeth in each jaw. 



The dorsal fin high and rounded, with eleven nearly subequal branched rays, and termi- 

 nating over the commencement of the anal rays. Pectorals pointed, placed low on the body, 

 with its middle rays longest, and extending to the seventh dorsal ray. Ventrals very feeble, 

 of seven very closely applied rays, with their tips extending to the anal. Anal fin higher than 

 long. Caudal fin broad and short, nearly even ; its margin slightly excavated. 



