Jordan and Evermann. Fishes of North America. 1495 



gg. Lower lip attached by a broad frenum; vertebra) 13 -f 16 ; gill 

 rakers short, stout, blunt, 5 + 11 ; anal basis below 10 cau- 

 dal vertebra. AMPHISTICHUS, 606. 

 ff. Teeth in a single series in each jaw. 



j. Dentigerous surface of lower pharyngeal flat or concave. 



k. Abdominal vertebra} 13 to 15 only, the abdomen much 

 shorter than the base of the long anal fin; anterior and 

 lateral pharyngeal teeth small, conic, the median and 

 posterior ones large, truncate molars; males with a 

 gland on some of the anterior anal rays, the anal basis 

 without angle, none of the rays modified to form a defi- 

 nite plate. 



I. Lower lip thin, normal, entire, with a frenum. 



m. Vertebnc 14 +18 or 19; anal basis below 9 caudal 

 vertebrae ; first haemal spine small, applied to 

 the second. EMBIOTOCA, 607. 



mm. Vertebrae 14 or 15 + 21 to 24 ; anal basis below 

 11 or more caudal vertebra?; first haemal 

 spine as long as second, sometimes approxi- 

 mated to the second. 



n. Caudal peduncle short and deep; caudal not 

 deeply forked. T^ENIOTOCA, 608. 



nn. Caudal peduncle long and slender, little com- 

 pressed ; caudal deeply forked. 



PHANERODON, 609. 



II. Lower lip without a frenum, very thick, lobed or incised 



behind ; gill rakers long ; vertebrae 14 -f 22 = 36. 



RHACOCHILUS, 610. 



kk. Abdominal vertebrae 17, caudal 19; abdomen very long, 

 much longer than the base of the short anal fin ; lips 

 large, entire, the lower with a frenum ; gill rakers slen- 

 der, short, 7 -f 13; anterior and lateral teeth of pharyn- 

 geals small, bluntly conic ; a triangular posterior patch 

 of larger teeth, all but the posterior row truncate, the 

 posterior row conic. HYPSURUS, 611. 



jj. Dentigerous surface of lower pharyngeals arched, the anterior 

 teeth much worn, the posterior not at all ; cutting surface of 

 anterior teeth flattened; that of the posterior teeth not faced ; 

 teeth of the upper pharyngeals similar to those of the lower 

 pharyngeals, but the posterior teeth of the upper pharyn- 

 geal applied to the anterior of the lower pharyngeal (the 

 posterior teeth above resembling the anterior teeth below ; 

 the anterior above, the posterior below) ; lips thin, normal, 

 with a frenum ; gill rakers slender. DAMALICHTHYS, 612. 



598. HYSTEROCARPUS, Gibbons. 



Hytterocarpus, GIBBONS, Daily Placer Times and Transcript, May 18, 1854, and in Proc. Ac. 



Nat. Sci. Phila. 1854, 124 (trasTa). 

 Sargosomus (AGASSIZ MS.) ALEXANDER AGASSIZ, Proc. Boat. Soc. Nat. Hist. 1861, 128 



(fluviatilis) . 

 Dacentrus, JORDAN, Bull. U. S. Geol. Surv., iv, 667, 1878 (lucens). 



Body ovate, the back strongly elevated and convex ; head small, the snout 

 projecting; mouth small, with 1 series of rather large, bluntly conical 

 teeth; the jaws about equal; lips not much enlarged, the lower forming 

 a free border, without frenuni; gill rakers moderate, widely set; branehi- 



