FISHES. 25 



20. SEMOTILUS SPECIOSUS, Grd. 

 GEN. REP. 283. PLATE LXI, FIGS. 1115. 



SPEC. CHAR. Body elongated, sub-fusiform in its outlines. Head constituting the fourth of the total length, the furcated 

 portion of the caudal excluded. Snout sub-conical; gape of the mouth oblique; posterior extremity of maxillar bone extending 

 to a vertical line drawn at the anterior rim of the pupil. Eye moderate size, sub-circular; its diameter entering five times in 

 the length of the side of the head. Anterior margin of dorsal fin nearer the extremity of the snout than the tip of the caudal. 

 Insertion of ventrals nearer the isthmus than the base of the caudal. Anal fin much deeper than long. Reddish brown above ; 

 yellowish or whitish beneath. Dorsal and caudal fin provided with a black spot at their base. 



176. Tributaries of Platte river, Nebraska. J. S. Bowman. 



21. GILA ELEGANS, B. & G. 

 GEN. REP. 286. 



SPEC. CHAR. Body very slender; tail very much attenuated. Head constituting the fifth of the total length. Eye small 

 sub-elliptical ; its diameter entering seven times in the length. Posterior extremity of maxillar bone extending to a vertical 

 line drawn in advance of the orbit. Anterior margin of dorsal fin nearer the extremity of the snout than the base of the 

 caudal. Base of anal fin entering about nine times in the total length. Origin of ventrals much nearer the extremity of the 

 snout than the base of the caudal. Reddish brown above ; metallic yellow beneath. 



249. Grand river, Utah. Mr. Kreuzfeld. 



22. TIGOMA OBESA, Grd. 

 GEN. REP. 290. 



SPEC. CHAR. Body short and compact; peduncle of the tail rather attenuated. Head small, constituting the fifth of the 

 total length. Snout abbreviated and rounded ; posterior extremity of maxillar bone extending to a vertical line drawn in front 

 of the orbit. Eye moderate sized, sub-circular ; its diameter entering a little over four times in the length of the side of the 

 head. Anterior margin of dorsal fin nearly equidistant between the extremity of the snout and the fork of the caudal fin. 

 Origin of ventrals somewhat nearer the insertion of the caudal than the extremity of the snout. Bluish grey above ; yellowish 

 white beneath, with a lateral reddish streak. 



215. Salt Lake Valley, Utah. J. S. Bowman. 



23. TIGOMA HUMBOLDTI, Grd. 

 GEN. REP. 291. 



SPEC. CHAR. Body rather short and deep, tapering gradually towards the peduncle of the tail. Head contained a little over 

 four times and a half in the total length. Snout thickish and rounded ; gape of mouth slightly oblique; posterior extremity of 

 maxillar bone extending to a vertical line drawn within the anterior rim of the orbit. Eye well developed, sub-circular ; its 

 diameter entering four times in the length of the side cf the head. Anterior margin of dorsal fin equidistant between the 

 extremity of the snout and the fork of the caudal. Origin of ventrals equidistant between the extremity of the snout and the 

 insertion of the caudal. Bluish or greyish black above; yellowish beneath. 



225. Humboldt river. J. S. Bowman. 



24. TIGOMA EGREGIA, Grd. 

 GEN. REP. 291. 



SPEC. CHAR. Body rather elongated, sub-fusiform in profile. Head contained four times in the length, the caudal fin 

 excluded. Snout sub-conical and thickish ; gape of the mouth slightly oblique ; jaws equal ; posterior extremity of the 

 maxillary extending to a vertical line drawn within the anterior rim of the orbit. Eye moderate sized, sub-circular ; j t8 

 diameter entering four times and a half in the length of the side of the head. Anterior margin of dorsal fin nearer the 

 extremity of the snout than the fork of the caudal. Origin of ventrals equidistant between the insertion of the caudal fin 

 and the extremity of the snout. Bluish black above ; yellowish orange beneath. 



226. Mr. Kreuzfeld. 



