94 HAPLOMI. 
Synopsis of the Mexican and Central-American Species. 
I. Dorsal fin with 7 to 12 rays, its origin posterior to that of the anal. (GampustA.) 
A. Anal fin similar to the dorsal, rounded or obtuse, the middle rays the longest. (? G. dr7- 
dentiger.) 
1. End of anal below anterior part or middle of dorsal (2); no dark cross-bars on the 
body. 
Diameter of eye 3 to 34 in the length of head (in specimens measuring up to 
70mm.) 2. 1 6 ee ee ee ee ee ww ee ew we we OL graaeilis. 
Diameter of eye 2} to 2? in the length of head (in specimens measuring up to 
5Omm.) 2. 2. 1 ee ee ee eek ke ee ew ee wR bonita. 
2. End of anal nearly below origin of dorsal. 
4 or 5 narrow blackish cross-bars on each side . . . 2 oe ew ew ee 6 8y fasciata. 
7 or 8 brownish vertical bars on the posterior part of the body 2 oe ee ww) A tridentiger. 
B. Anal fin dissimilar to the dorsal, pointed, the anterior rays the longest. 
1. Pectoral nearly as long as the head, extending to the origin of anal . 5. micaraguensis. 
2. Pectoral shorter than the head, not reaching the anal. 
a. Dorsal with 8 or 9 rays. 
Length of head 4 to 44 in the length of the fish (in specimens of 25 to 50 mm.) ; 
29 to 31 scales in a longitudinal series . . . 2. 1. ee © ee 6. infans. 
Length of head 3 to 82 in the length of the fish (in specimens measuring up 
to 45 mm.) ; 28 scales in a longitudinal series . . . . . . . + + «7. episcopit. 
b. Dorsal with 10 tol2 rays . 2. 2 1 ew ee ee ee ee 8 annectens. 
II. Dorsal fin with 1] to 17 rays, its origin in advance of that of the anal. (PsrupoxIPHoPHORWS.) 
A. Origin of anal below or a little in advance of middle of dorsal; no dark spot above the 
pectoral. 
Dorsal with 12 to 14 rays, its origin equidistant from tip of snout and base or 
anterior part of caudal. . 2 1 ee ee ee ee we eee D terrabensis. 
B. Origin of anal below anterior part of dorsal ; a dark spot above the pectoral. 
Dorsal with 11 to 18 rays, its origin equidistant from tip of snout and middle 
or posterior part of caudal. . . . . . . » oe we ew ew ew + 10. gonesiz. 
Dorsal with 13 to 17 rays, its origin about equidistant from tip of snout and 
base ofcaudal . 2. 2... ee ee eee ee ee ee ee LL. btmaculata. 
1. Gambusia gracilis*. 
Xiphophorus gracilis, Heck. Sitzungsb. Ak. Wien, i. 1848, p. 300, t. 9. figs. 83-4". 
Gambusia affinis, Jord. & Everm. Bull. U.S. Nat. Mus. xlvii. 1896, p. 680* ; Meek, Publ. Columbian 
Mus., Zool. v. 1904, p. 180°. 
Gambusia nobilis, Jord. & Everm. t. c. p. 682°. 
Gambusia gracilis, Jord. & Everm. t. c. p. 683”. 
Depth of body 8 to 4 in the length, length of head 33 to 4. Snout as long or nearly as long as eye, the 
diameter of which is 3-34 in the length of head. Interorbital width about equal to the distance from 
* For the extensive synonymy of this species, see Jord. & Everm. pp. 681-683, and Garm. Mem. Mus. 
Comp. Zool. xix. 1895, pp. 82-85 (G. holbrookit, patruelis, and gracilis). 
