240 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY IV. 
Head conic, the profile steep, the muzzle short and rather pointed. 
Mouth suiallj oblique, the jaws nearly equal, the upper lii) on the level 
of the lower part of the pupil, the maxillary scarcely reaching to front 
of eye; isthmus very narrow; preorbital nearly as deep as long. Eye 
small, anterior, o in head. Fins low. Dorsal fin opposite ventrals, 
nearer caudal than snout; caudal fin short, little forked, scarcely broader 
tiian the very deep caudal peduncle, the spines of the caudal vertebrm 
veiy strong. Scales large, rather closely imbricated, their exposed sur- 
faces rather deeper than long; 2(5 scales before dorsal. Lateral line 
decurved. Color brownish; sides white; young spotted above; scales 
everywhere with dark dots; fins plain. Head 4J; depth 3. 1). 8; A. 8; 
scales 9-5()-7 ; teeth 2, 5-4, 2. L. 12 inches. Eivers of California; very 
abundant. One of the most peculiar of our Gyprimdw, but hardly consti- 
tuting a distinct genus. 
{Lavinia cmssica)ida Baird &Girard, Proc. Acad. Nat. Sci. Pliila. 1854, 137 (Aiigu.st); 
Siboma crassicauda Girard, Proc. Acad. Nat. Sci. PUila. 1856, 208, and U. S. Pac. R. 
R. Surv'. Fisli, 296: LeucisctiH crassicauda Gliuther, vii, 243: Lcnciscus (jibbosus Ayres, 
Daily Placer Tioies and Transcript, May 30, 1854: Lavinia gihbosa Ayres, Proc. Cal. 
Acad. Sci. 1854, 20.) 
Teeth with evident grinding surface.* (Squalius.) 
c. Robust species; depth 3 to 3|- in length; lateral line less than 60. 
395. S. rliomaleiis .Jor. & Gilli. 
Body very robust, elevated anteriorly, the si<les compressed, although 
the back is very broad. Head broad, the profile concave as seen from 
the side, the iuterorbital space flattish, scarcely raised above the eye. 
Snout bi’oad, elevated at tip, premaxillary on the level of pupil. Mouth 
very oblique, the mandible much projecting, maxillary reaching front of 
eye. Eye small, anterior, 1| in snout, 7 in head ; isthmus very narrow. 
Scales large, subequal, broadly exposed, firm. Lateral line decurt ed. 
Dorsal nearly median, inserted directly over ventrals. Caudal evenly 
forked, the peduncle long and deep. Pectorals short, extending three- 
fifths the distance to ventrals, ventrals about to vent. Lower fins short. 
Color blackish ; everywhere dark. Head 3i- ; depth 34. 1). 0 ; A. 8 ; 
scales 10-55-5 ; teeth 2, 5-4, 2, short and stout, one of them with grinding 
surface. L. 12 inches. Utah Lake. One of the largest and best marked 
species. 
(Jordan & Gilbert, Proc. U. S. Nat. Mus. 1880, 461.) 
A variable character in this group. 
