106 . HAPLOMI. 



the fin, below wtiieli are longitudinal stripes and above which are numerous smaller spots ; caudal with 

 series of small spots. 



Hah. South Carolina to Tamaulipas : 



Pensacola in Florida ; New Orleans ^ '^^ ; Indianola ^ and Brownsville ' in Texas ; 

 Matamoros '^^, Palo Alto'^, La Vega ^, and Tampico ■-> in Tamaulipas. 



Here described from several specimens, measuring up to 75 mm. in total length, 

 from New Orleans, Pensacola, and Tampico. Garman's plate illustrates strikingly 

 the diflFerences between the sexes and the changes during growth in this species, 

 which attains a length of 100 mm. 



2. Mollienisia petenensis. 



Mollienisia petenensis, Giintli. Cat. Fish. vi. p. 348 (1866) \ and Trans. Zool. Soc. vi. 1868, p. 4-85, 

 t. 86. figs. 1-3"; Jord. & Everm. Bull. U.S. Nat. Mus. xlvii. 1896, p. 700 '. 



Depth of bod}- 2| to 3 in the length, length of head 4. 28 to 30 scales in a longitudinal series. Dorsal 15-10. 

 Anal 9. Caudal rounded or subtrnncate, in the males with the lower angle pointed and slightly 

 produced. Males with a small dark spot on each scale of the upper and posterior piarts of the bodj' and 

 with the lower edge of the caudal blackish ; dorsal fin coloured as in 21. latipiana. 



Hal). Guatemala, Lake Peten {Salvia) i ". 



Here described from the types, six specimens, measuring up to 130 mm. in total 

 length. This species is very close to the preceding, but it attains a larger size and is 

 distinguished by the form of the caudal in the males, which suggests relationship with 

 Xiphajjlwrm. 



15. XIPHOPIIORUS, Heck., 184S. 



Xiphophorus, Jord. & Everm. Bull. U.S. Nat. Mus. xlvii. 1896, p. 701. 



Scarcel)' generioall}' distinct from Pn'cuV/a and J/o?/tf>ii,s7'«. Dorsal with 11 to l.j rays, higher but not much 

 longer in the males than in the females. Males with the lower rays of tlie caudal fin produced to form a, 

 long pointed appendage. 



Hah. Tamaulipas to British Honduras. 



The five closely allied species of this genus agree in the following features : — Snout 

 as long as or a little shorter than eye, the diameter of which is 3 to 3^ in the length 

 of head, interorbital width If to ly. Origin of dorsal about equidistant from tip of 

 snout and base of caudal, well in advance of that of the anal ( $ ). Pectoral nearly as 

 long as the head. Caudal appendage of the males pale, with black edges. 



Syno2)sis of the Species. 



I. Anal with 6 to 8 rays 1. montezuuue. 



II. Anal with 8 to 10 rays. 



A. Depth of body 3-1 in tlic length. 



1. Least depth of caudal peduncle not greater than the distance from 



anterior margin of eye to free edge of opereulum 2. helleri. 



