PCECILIA. 101 
Synopsis of the Species *. 
I. Origin of anal in advance of that of the dorsal. 
Dorsal 8. Anal 7. 26 scales ina longitudinal series . . . . . . . . . LJ. spilurus. 
Dorsal 7-9. Anal 9-11. 27 to 30 scales in a longitudinal series . . . . . 2. occidentalis. 
Dorsal 9-10. Anal 8-9. 80 to 33 scales in a longitudinal series . . . . . 3. elongata. 
II. Origin of anal below or behind that of the dorsal. 
A. Origin of anal below or a little behind that of the dorsal; origin of dorsal equidistant from 
tip of snout and middle or posterior part of caudal; 26 to 30 scales in a longitudinal 
series. 
Free edge of dorsal fin convex . 1 1 ee ee ee ee ee ee ee A sphenops. 
Free edge of dorsal fin straight . 5. salvatoris. 
B. Origin of anal below fourth or fifth dorsal ray; origin of dorsal equi- 
distant from tip of snout and base of caudal; 28 to 30 scales in a 
longitudinal series 6. petenensis. 
C. Origin of anal below the middle of dorsal; origin of dorsal equidistant from tip of snout 
and anterior part of caudal; 23 to 27 scales in a longitudinal series. 
Depth of body about 2? in the length, length of head about 4 (in specimens of 
5Omm.) . 2 ee ee ee ee ee ee ee ee 7. COuChiANA. 
Depth of body 2 to 22 in the length, length of head 3} to 33 (in specimens of 
60mm.) . 2. 6 ee ee ee ee ee ee ee wee 8 maculata. 
1. Pecilia spilurus. 
Pecilia spilurus, Gunth. Cat. Fish. vi. p. 345 (1866)*; Jord. & Everm. Bull. U.S. Nat. Mus. 
xlvii. 1896, p. 697°. 
Depth of body 33 in the length, length of head 4. Snout a little shorter than eye, the diameter of which is 
34 in the length of head. Interorbital width equal to the distance from posterior margin of pupil to 
free edge of operculum. 26 scales in a longitudinal series. Dorsal 8; origin about equidistant from tip 
of snout and posterior end of caudal. Anal 7; origin in advance of that of the dorsal( 2). Least depth 
of caudal peduncle the length of head. A blackish spot on each side of the upper part of the tail, at the 
base of the caudal fin. 
Hab. Cantrat America (Sallé 1). 
Here described from the type, the only specimen known, 60 mm. in total length. 
2. Peecilia occidentalis. 
Heterandria occidentalis, Baird & Girard, Proc. Ac. Philad. 1853, p. 390’; Jord. & Everm, Bull. 
U.S. Nat. Mus. xlvii. 1896, p. 689°. 
Girardinus occidentalis, Givard, U.S. Mex. Bound. Surv., Fishes, p. 73, t. 39. figg. 16-19°, and 
Proc. Ac. Philad. 1859, p. 119%. 
Girardinus sonorensis, Girard, Proc. Ac. Philad. 1858, p. 120°. 
* This synopsis is based on female specimens only. The males of some of the species have not yet been 
described. 
