THE CYPRINODONTS. 69 



JENYNSIINjE. 

 JENYNSIA. 



Jenynsia Gthr., 1866, Cat., VI, 331, — 18S0, Intr., 616. 



Fitzroyia Gthr., 1866, Cat., VI, 307. 



Jenynsiina Gthr., 1866, Cat. VI, 300 ; GUI, 189i, Mem. Nat. Acad., VT, 133. 



Intermediate in shape between Fundulus and Poecilia, deep across the 

 belly and in the caudal region. Mouth medium, oblique, lower jaw longer, 

 upper protractile, symphyses rather firm. Teeth in bands, outer series 

 larger, tricuspid. Snout not produced. Dorsal and anal behind the middle 

 of the length, opposed, the latter originating a little backward of the former 

 in both sexes, modified and possessing a tube in the male. Scales medium. 

 Intestine longer than the body. Males rights and lefts. 



Jenynsia lineata. 



Plate I. Fig. 7, 8; Plate VIll. Fig. 2, 3, males. 



Lebias lineata Jenyns, 1842, Beagle Zool., Fish, 116, pi. 22, fig. 2. 



Jenynsia lineata Gthr., 1866, Cat., VI, 331; Perug., 1891, Aim. Mus. Civ., Gen., (2) X, 652; Eig., 

 1891, P. U. S. Mus., XIV, 65,-1894, Ann. N. Y. Ac, VII, 635. 



Cyprinodon lineatus Blkr., 1860, Cypr., 484. 



Lebias multidentata Jen., 1842, 1. c., 117, pi. 22, fig. 3. 



Fitzroyia multidentata Gthr., 1866, Cat., VI, 307- 



Cyprinodon multidentatus Blkr., 1860, 1. c., 484. 



Pcecilia punctata Val., 1846, C. V. Poiss., XVIII, 133 ; Blkr., 1860, 1. c, 486; Gthr., 1866, Cat., VI, 

 347 ; Eig., 1891, P. U. S. Mus., XIV, 65. 



Xiphophoriis Heckelii Weyenb., 1874, Ned. Kon. Ak. Wetens., VIIT, — 1875, Per. Zool. Argent., p. 11, 

 pi. 1 and 2, — , 1876, Nuev. Pesc. Mus. Nac., p. 17, pi. 4, fig. 15-16 ; Eig., 1893, P. U. S. Mus., 54. 



Xiphophorus obscurus Weyenb,, 1876, Nuev. Pesc., p. 18, pi. 4, fig. 17, 18. 



Xiphophorus minor Weyenb., 1876, Nuev. Pesc, p. 20, pi. 4, fig. 19. 



B. 5 ; D. 8-9; A. 9-10 ; V. 6 ; P. 15-16 ; LI. 29 ; Ltr. 8-9 ; Vert. 14+17. 



Form somewhat like that of Zygonectes but slightly deeper and more 

 compressed posteriorly. Back not much arched, belly prominent. Head 

 tapering, about two sevenths of the length without the caudal. Snout as 

 long as the eye, blunt. Eye large, once in the snout, one and one half times 

 in the interorbital space, three and a half times in the head. Mouth rather 

 narrow, oblique, lower jaw longer, upper protractile, chin steep. Teeth small, 

 in bands, tricuspid, outer series larger. Pharyngeal teeth hooked, with a 

 shoulder. Excepting the caudal the fins are small. First ray of dorsal 

 midway from head to base of caudal, over front edge of vent, half as long 

 as second ray. Origin of anal below third or fourth dorsal ray. On breed- 



