FAMILY XL PCECILIID^E. 157 



teeth pointed and loose, followed by a band of smaller conical pointed 

 teeth, eye large, 3 in head; origin of dorsal fin well in advance of the 

 anal, midway between base of caudal fin and middle of snout; base 

 of dorsal i| in head; longest dorsal ray if (?) to if (5) in head; 

 pectoral if in head; ventrals i^; caudal sub-truncate; caudal 

 appendage of male pointed, its length if in the length of the body; 

 caudal peduncle slender, its least depth 2^ in head; modified anal 

 of the male short and thick, its length i^ in head, a notch on under 

 side near its tip. 



Color of female olive brown above, nearly plain white below, a 

 narrow lateral band passing around snout on upper half of the body ; 

 each scale with a dark center, giving faint brownish lines on the sides ; 

 dorsal fin with two rows of black spots near the base; other fins plain; 

 color of male similar to that of the female, except the dark lateral 

 band extending on caudal fin and forming the upper black margin 

 of caudal appendage; a second lateral band from lower angle of 

 pectoral to origin of the anal fin, and a dark streak on ventral surface 

 of caudal peduncle, forming the lower black margin of caudal appen- 

 dage ; in life the middle of the caudal appendage and the lighter portion 

 of lower half of the body is a bright yellow; dorsal fin of both sexes 

 spotted. Length about 4 inches. 



This species is smaller than X. helleri; it is more slender and the 

 male has the second lateral band from angle of pectoral to origin of 

 the anal fin. Known only from the type locality, where it is abundant. 



149. Xiphophorus helleri Heckel. 



Xiphophorus helleri Heckel, Sitz. Akad. Wiss. Wen, 1898, 163; 

 Rio Chisoy; Cordoba: Gunther, Fishes Cent. Amer., 485, pi. 87, 

 figs. 2-6, 1869; Rio Chisoy: Garman, Memoirs Musi Comp. 

 Zool., 1895, 68, pi. iv, fig. 14, teeth, pi. vm, fig. 4; Mexico 

 and Central America: Jordan & Evermann, Bull. 47, U. S. 

 Nat. Mus., 1896, 701. 

 Xiphophorus helleri Var. g Giinther, Cat., vi, 350, 1866; Rio 



Chisoy, Guatemala. 

 Xiphophorus guntheri Jordan & Evermann, Bull. 47, U. S. Nat. 



Mus., 1896, 702. 



Lowland streams of southern Mexico and Guatemala, which 

 empty into the Gulf of Mexico. (Cordoba; Otopa; Motzorongo; 

 Refugio; El Hule; Obispo; Sanborn.) 



Head 4f to 4f; depth 3 to 3^ ; D. 12 or 13; A. 8 or 9; scales 

 9-30. Body elongate, compressed; head small; interorbital slightly 

 convex, if in head; snout 3^ in head; eye 3^3 in head; origin of 

 dorsal fin slightly nearer tip of snout than base of caudal, about > 



