670 Bulletin 47, United States National Museum. 



tip of snout to the nape, the region thence to the dorsal gibbous, espe- 

 cially in the larger examples, the caudal peduncle comparatively long and 

 slender, about as long as head. Anterior teeth large, firmly fixed, all 

 bicuspid or Y-shaped, in a single series ; a band of minute villiform teeth 

 behind them, at least in upper jaw. Mandible not extending back to 

 front of eye. Interorbital area wide, very nearly half head. Scales 

 rather small, those on top of head not much longer than others ; humeral 

 scale not enlarged. Opercle connected by membrane to shoulder 

 girdle from upper base of pectoral upward, as in Cyprinodon. Insertion 

 of dorsal very far back, midway between base of caudal and base of pec- 

 toral; first ray of dorsal very slender and articulate, not at all spine- 

 like ; dorsal fin low, not so high as long, its base If in head ; anal 

 inserted below seventh ray of dorsal ; pectorals If in head ; ventrals 2 

 in head ; caudal obliquely truncate, very slightly emarginate, the upper 

 lobe about longer than the lower, 1J in head ; upper lobe usually more 

 or less sharply angular ; lower lobe rounded. Males with the sides pro- 

 fusely mottled with darker, sometimes nearly plain ; vertical fins each 

 with several brownish bars and blotches and each with a dusky sub- 

 terminal bar ; a narrow dark line along middle of each row of scales on 

 the back. Females with several short, dark bars on the posterior half of 

 the body, the fins colored as in the male; some small, dark specks on 

 caudal peduncle. About Cape San Lucas; locally abundant ; and about 

 Colima. (furca, fork; dens, tooth.) 



Characodon furcidens, JORDAN & GILBERT, Proc. U. S. Nat. Mus., 1882, 354, near Cape San 

 Lucas.* (Type, Nos. 9071 and 30971. Coll. Xantus.) 



307. CYPRINODON, Lacepede. 



(PURSY MINNOWS.) 



Cyprinodon, LACKPEDE, Hist. Nat. Poiss., v, 48G, 1803, (variegatus). 

 Prinodon,^- KAFINESQUE, Analyse de la Nature, 1815, 88, (variegatus). 

 Tnfarcius, POEY, Memorias, 11, 306, 1861, (riverendi). 



Body very short and stout, the back elevated. Mouth small, the bones 

 of the jaws well formed. Snout short. Teeth moderate, incisor-like, tri- 

 cuspid, in a single series. Scales very large. Dorsal fin moderate, 

 inserted in advance of front of anal, its first ray riot enlarged ; anal 

 smaller ; ventral fins small, occasionally wanting in specimens from desert 

 pools. Intestinal canal little longer than body. Gill membranes con- 

 siderably united, free from the isthmus. Gill openings restricted, the 

 opercle above adnate to the shoulder girdle. Chubby little fishes, inhabit- 

 ing the brackish waters of Middle America,t sometimes living in warm 

 salt springs, their colors generally brilliant. Oviparous, the sexes simi- 

 lar except in color. (Kvirpivoq, carp ; 6Jo>f, tooth.) 



* Probably from the lagoons at La Paz. 



f- This name was offered as a substitute for Cyprinodon, the latter being regarded as too long. 



{ The European and African species commonly referred to this genus seem to represent a dis- 

 tinct generic type, Lebias, Cuvier, ( = Micromugil= Aphanius), distinguished by the freedom of 

 the opercle, and by the more elongate form, resembling Fundulus. Of these species, Lebias cal- 

 aritanus from the Mediterranean is the best known, and is the only one on which these characters 

 have been verified. 



