668 Bulletin 47, United States National Museum. 



in a single series, with a band of villiform teeth behind them. Scales 

 moderate. Insertion of dorsal nearly opposite that of anal. Intestinal 

 canal short ; bones of jaws well united. Small fishes of the fresh waters 

 of Mexico and Central America. (%upat;, a sharp stake ; btovs, tooth.) 

 a. Scales rather large, 32 to 35 in longitudinal series. 



b. Dorsal fin small, of 10 or It rays; anal rays 13 to 16; scales 35-12; a dark lateral band, 

 sometimes broken into spots. LATERALIS, 981. 



bb. Dorsal fin large, of 13 to 16 rays; depth 3 to 3% in length. 



c. Dorsal rays 1C; anal 16; scales 32-11; body with two lateral stripes, the second 



beginning with front of anal. BILINEATUS, 982. 



cc. Dorsal rays 13 or 14; anal 15 or 16; scales 36-15; males with a faint dark lateral 



stripe made of dark blotches; female without stripe, irregularly blotched or 



spotted. VABIATUS, 983. 



aa. Scales rather small, about 50 in a longitudinal series; dorsal rays 16; anal 13; depth 3f in 



length; sides mottled or barred, the fins with dark bars. FURCIDENS, 984. 



981. CHARACODON LATEBALIS, GUnther. 



Head 3i ; depth 3 ; eye 4. D. 10 or 11 ; A. 13 in female, 15 or 16 in 

 male; scales 35-12. Body rather elevated, with the neck somewhat 

 arched. Head thick and broad, with the snout obtuse, as long as the eye. 

 Mandible ascending obliquely, longer than eye. About 20 smallish teeth 

 in each jaw, their apex indistinctly notched. Interorbital space flat, 

 its width being 2^ in head. Origin of dorsal fin a little nearer end 

 of caudal than to occiput, a little behind that of the anal ; both fins 

 small and rounded; in the male the six anterior rays are of nearly equal 

 length, but considerably shorter than the following, forming a very dis- 

 tinct portion of the fin ; all these rays are very closely set ; caudal fin 

 small, truncate, or slightly convex ; distance between dorsal and caudal 

 somewhat more than least depth of tail, and equal to distance between 

 eye and gill opening; pectoral obtuse, not quite reaching ventral; 

 ventral small, not quite extending to the vent. Brownish olive 

 (in spirits), with a darker band running from the eye to the root of 

 the caudal ; this band sometimes broken up into a more or less regular 

 series of brownish-black spots. In general habits very similar to a 

 Cyprinodon. Central America. (Gunther); not seen by us. (lateralis, 

 pertaining to the side.) 



Cltaracodon laterals, GfJNTHER, Cat., vi, 308, 1866, Central America; (Coll. Dr. Seemann); 

 GUNTHER, Fishes Central Arner., 480, pi. 82, fig. 2, 1886. 



982. CHARACODON BILINEATUS, Bean. 



Head 3f ; depth 3 ; eye 4. D. 16 ; A. 16 ; scales 32-11. Head broad and 

 depressed, the interorbital space being nearly flat, the nape moderately 

 arched. Snout short, rather shorter than eye ; the lower jaw somewhat 

 prominent ; upper jaw moderately protractile. About 20 bicuspid teeth 

 in the outer series of each jaw ; villiform teeth behind the incisors evi- 

 dent ; mandible nearly vertical when the mouth is closed, nearly reach- 

 ing eye. Eye scarcely more than $ interorbital width. Scales on top of 

 head somewhat enlarged. Opercle connected by membrane to the shoul- 

 der girdle, beginning at a point slightly above upper edge of pectoral. 

 Insertion of the dorsal midway between the posterior margin of the eye 



