Family XI. Poeciliid^e. 133 



Head 3X; depth 3^; D. 7 or 8; A. 9; scales 8-32. Body elongate, 

 somewhat compressed, profile from tip of snout to origin of dorsal a 

 straight line; head moderate, mouth rather large, oblique; the lower 

 jaw the longer; teeth conical, in a band, the outer series enlarged; 

 snout 3^ in head; eye 3 in head; origin of dorsal to base of caudal \]/ 2 

 in its distance from tip of snout, about midway between base of caudal 

 and base of pectoral fin ; anal (in females) well in advance of dorsal ; 

 pectoral 1^ in head; ventral 2^; caudal fin slightly rounded, least 

 depth of caudal peduncle if in head; alimentary canal shorter than 

 length of fish; peritoneum black; vertebras 15 + 16=31. 



Color dark olivaceous above, white below; on darker portion of the 

 body each scale has a light margin forming lateral stripes along the 

 rows of scales; caudal fin usually tipped with black; a narrow dark 

 streak on middle of caudal peduncle, this more prominent on the 

 males; iris black. Length about 2^ inches. 



One female 2.36 inches in length contained 38 partially hatched 

 eggs. 



The young are probably born in May. 



53. Paragambusia gen. nov. 



Type, Gambusia nicaraguensis Gtinther. 



Anal fin falcate, its first 3 rays much produced, longer than 

 head, otherwise essentially as in Gambusia. 



123. Paragambusia nicaraguensis (Gtinther). 



Gambusia nicaraguensis Gtinther, Cat., vi, 336, 1866; Lake of 

 Nicaragua: Gtinther, Fishes Cent. Amer., 483, pi. 82, fig. 3, 

 1869; Lake of Nicaragua: Jordan & Evermann, Bull. 47, 

 U. S. Nat. Mus., 1896, 682. 



Southern Mexico and Central America. (Otopa; Boca del Rio; El 

 Hule; Obispo; Perez.) 



Head 3^; depth 2%; D. 6; A. 10; scales 10-26. Body rather 

 robust, much compressed; head small, depressed; interorbital flat, i}{ 

 in head; snout wedge-shaped, 3^ in head; teeth pointed; diameter of 

 eye 3 in head; origin of dorsal fin (9) almost entirely behind anal, its 

 distance from base of caudal 2 in its distance from tip of snout ; anal 

 fin of female with its first 3 or 4 rays produced and falciform, the longest 

 ray equaling distance from tip of snout to base of pectoral fin ; pectoral 

 fin equals length of head; ventral 2 in head, one of its rays slightly 

 produced; caudal fin rounded; least depth of caudal peduncle i>{ in 

 head ; peritoneum black ; alimentary canal less than length of the fish. 



