THE CYPRINODONTS. 61 



Poecilia occidentalis. 



Plate V. Fig. 5, teeth. 



Heterandria occidental^ B. & G, 1854, P. Phil. Ac, VI (1853), 390; Blk., 1860, Cjpr., 485 ; Jor., 

 1887, R. U. S. F. Com., 838. 



Girwrdinus occidentalis Grd., 1859, P. Phil. Ac, 119, - Mex. Bd. Sur. Pish, 73, pi. 39, fig. 16-19 ; Blk., 

 1860, CTOr. 484; Trosch., 1865, Wirb. Mex., 108; Gth., 1866, Cat., VI, 354; Jor. & C, 1877, B. Buf. Sec, 

 III, 142; Jor., 1878, B. U. S. G. Sur., IV, 434; Jor. & G., 1882, B. 16 U. S. Mus., 349; Eig., 1893, P. 

 U. S. Mus., XVI, 58. 



Girardima sonoriensis Grd., 1859, P. Phil. Ac, 120; Blk., 1860, Cypr., 484; GU... 1866, Cat., VI, 355 ; 

 Cope & Y., 1875, Wlieel. Exp. ZooL.V, 695; Jor. &C., 1877; B. Buf. Soc, III, 142 ; Jor., 1878. B. U. S. G. 

 Sur., IV, 434. 



B. 5 ; D. 8 ; A. 10-11 ; V. 6 ; P. 15 ; LI. 27-30 ; Ltr. 8 ; Vert. 15+15. 



Shaped much like Gambusia Holbrookii. Stout anteriorly, compressed 

 backward, depressed on the head. Head broad, slightly arched across the 

 crown, less than the depth of the body, less than one fourth of the length 

 from snout to base of caudal. Snout short, narrowed forward, blunt ; chin 

 steep. Mouth narrow, not as wide as the eye ; lower jaw longer ; upper 

 short, protractile. Teeth in the outer series long, hooked spatuliform, com- 

 pressed in the basal half, broadened toward the summit ; inner series small, 

 pointed, slightly hooked ; pharyngeal grouped in short rows. Eye moderate, 

 as long as snout, little more than half of interorbital space, two sevenths of 

 the head. Dorsal small, originating midway from base of pectoral to base of 

 caudal or above the middle of the base of the anal. Caudal as long as the 

 head, median rays longer. 



Light yellowish to olivaceous, puncticulate with dark, hind edges of scales 

 darker, opercle silvery, sides of belly golden to silvery, middle of belly and 

 throat silvery. A dark band one scale in width from head to middle of cau- 

 dal. The middle of the band is traversed by a black line ; another line is 

 found behind the anal ; and a third behind the dorsal. Anal aperture in a 

 black spot. Fins plain to puncticulate with dark, or with a darkish trans- 

 verse band near the base of dorsal and anal. On one the dorsal has a dis- 

 tinct spot of black at the bases of the posterior rays. Whether the anal 

 process of the male is short and whether the jaws are loosely joined cannot 

 be decided from these specimens ; this leaves us in doubt whether the species 

 may not belong to Glaridodon to which it makes considerable approaches. 

 San Bernardino Creek, Mex. ; Nickson, Arizona. 



