THE CYPRINODONTS. 59 



base of the caudal. Snout broad, subtruncate, nearly or quite as long as tlic 

 eye. Mouth moderately wide, directed upward ; lower jaws longer, loosely 

 joined ; upper shorter, protractile. Outer series of teeth slender, movable, 

 narrowed toward the base, widened toward the apex, hooked ; inner in 

 bands, small, tricuspid. Eye large, about as long as snout or longer in 

 young, half of interorbital space, two sevenths of head. Fins medium, ex- 

 cepting caudal, which is large. Dorsal origin little behind the middle of the 

 length, without the caudal. Anal origin a short distance behind that of dor- 

 sal in females ; fin advanced and modified in males, process shorter than head 

 and bearing a short fleshy lobe below its extremity. The first ray of the 

 dorsal is a trifle farther forward in the male, and the fin is higher and 

 broader. Yentrals small, second ray elongate in males. Caudal deep, nearly 

 as long as head, truncate. Scales large. Intestine long. 



Olivaceous, darker on back and top of head, lighter to silvery downward 

 on the flanks and beneath, edges of scales darker. Cheeks silvery. With or 

 without vittse, formed by a spot on each scale of one to several series, on the 

 middle of the flank. Without or with vertical narrow bars of brownish on 

 the sides, a longitudinal silvery streak, or a brownish tint along the middle 

 of the flank. Fins plain to puncticulate or spotted with black, or dorsal and 

 caudal with one to several irregular transverse series of spots. In the breed- 

 ing season the dorsal of the male becomes longer ; in cases it reaches the 

 short rays of the caudal and the fin is blotched with black and yellow. Some 

 individuals have large irregular blotches of black scattered over the sides. 

 Largest female four and one fourth and largest male two and one eighth 

 inches. Cuba. 



Poecilia sphenops. 



Plate IV. Fig. 13, teeth. 



Pxcilia sphenops Ya\., 1846, C. V. Poiss., XVIH, 130, pi. 526; Blk., 1860, Cypr., 486; Gth., 1866, 

 Cat., VI, 343 ; Eig., 1S93, P. U. S. Mus., XVI, 57. 



Limia couchiana Grd., 1859, P. Phil. Ac, 116. 



Gambusia couchiana Blk., 18G0, Cypr., 485. 



Pacilia couchii Gth., ISCG, Cat., VI, 347 ; Eig., 1S93, P. U. S. Mus., XVI, 57. 



MolUnesia couchiana Jov. & C, 1877, B. Buf. Soc, III, 142; Jor., 1878, B. U. S. G. Sur., IV, 434. 



Pcecilia couchiana Jor., 1887, R. U. S. F. Com., 838 ; Everm. & K., 1894, B. U. S. E. Com., pp. 76, 

 84, 87. 89, 92, 108. 



Pcecilia mcxicana Steind., 1863, Sb. Ak. Wien, XLVIII, 178, pi. IV., fig. 1, 1 a ; Gth., 1866, Cat., VI, 

 340; Tiosch , 1865, Syst. Wirb. Mex., 104; Eig., 1893, P. U. S. Mus., X'VT:, 57. 



Poecilia thermalis Steind., 1863. Sb. Ak. Wien, XLVIII, 181, pi. 4, fig. 3,3a; Trosch., 1865, Wirb. 

 Hex., 104 ; Gth., 1866, Cat., VI, 341 ; Eig., 189.3, P. U. S. Mus., XVI, 57- 



Gambusia modesta Trosch., 1865, Wirb. Mex., 105. 



Gambusia plumbea Trosch., 1865, Wirb. Max., 106. 



