DESCRIPTION OF A NEW SPECIES OF KILLIFISH, LUCANIA 

 BROWNI, FROM A HOT SPRING IN LOWT^R CALI- 

 FORNIA. 



By David Starr Jordan and Robert Earl Richardson, 



Of Stanford UniviTsitij, California. 



We have recenth^ received from Mr. Herbert Brown, of Tucson, 

 Arizona, 6 specimens of a small killifish of the genus Lucania, taken by 

 Mr. Brown from a hot-water sprino; in northeastern Lower California. 

 Being unable to identify these with any hitherto described species, 

 we here describe them as new, and propose for them the name of 

 Lucania browni. 



LUCANIA BROWNI, new species. 



Head 3.3 in length without caudal; depth 3.3 (3.5 in males) ; D. 10, 

 A. 10, scales 28 (25); depth of caudal peduncle 1.9 in head; breadth 

 of head 1.6; eye 3; interorbital space equal to eye; nose 4 in head; 

 mouth very small and quite oblique; maxillary equals pupil, the tip 

 of the upper lip slightly below upper rim of pupil ; teeth sharp, pointed, 

 equal, in a single row on each jaw; gill membranes connected for a 

 short distance, the gill openings not restricted above; intestine not 

 longer than body; dorsal inserted slightly behind ventrals, a little 

 nearer base of caudal than end of snout; anal fin not modified into an 

 intromittent organ in males, its length when depressed, in female 1.3 

 in head, in male equal to head; pectoral 1.4 in head; ventrals very 

 small, 2.75 in head. 



Color of fi'esh specimens in formalin: Females olivaceous, each 

 side of Ijody with about 8 large Idotches of darker color, forming a 

 broken lateral band in adults; the blotches continued downward on 

 bell}'^ as cross bands in half-grown sj^ecimens; 3 diffuse clusters of 

 punctulations on the belly just in front of and above anal fin; dorsal 

 punctulated with dusky in both membranes and rays, with a con- 

 spicuous dark blotch behind, between the sixth and tenth rays; 

 caudal pale,mth two crescentric cross bands across its base, the inter- 

 space between them pale; ventrals and anal pale; pectorals ol)Scurely 



Proceedings U. S. National Museum, Vol. XXXlll— No. 1572. 



