THE CYPRINODONTS. 69 
JENYNSUNZ. 
JENYNSIA, 
Jenyasia Gthr., 1866, Cat., VI, 331, — 1880, Intr., 616. 
Fitzroyia Gthr., 1866, Cat., VI, 307. 
Jenynsiina Gthr., 1866, Cat. VI, 300 ; Gill, 1894, Mem. Nat. Acad., VI, 133. 
Intermediate in shape between Fundulus and Peecilia, 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 IL. Fig. 7, 8; Plate VIII. Fig. 2, 3, males. 
Lebias lineata Jenyns, 1842, Beagle Zool., Fish, 116, pl. 22, fig. 2. 
Jenynsia lineata Gthr., 1866, Cat., VI, 331; Perug., 1891, Ann. 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, |. c., 117, pl. 22, fig. 3. 
Fitzroyia multidentata Gthr., 1866, Cat., VI, 307. 
Cyprinodon multidentatus Bikr., 1860, 1. c., 484. 
Pacilia 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. 
Xiphophorus Heckelii Weyenb., 1874, Ned. Kon. Ak. Wetens., VIII, —1875, Per. Zool. Argent., p. 11, 
pl. 1 and 2, —, 1876, Nuev. Pesce. Mus. Nac., p. 17, pl. 4, fig. 15-16; Eig., 1893, P. U. S. Mus., 54. 
Xiphophorus obscurus Weyenb., 1876, Nuev. Pesc., p. 18, pl. 4, fig. 17, 18. 
Xiphophorus minor Weyenb., 1876, Nuev. Pesc., p. 20, pl. 4, fig. 19. 
B.5; D. 8-9; A. 9-10; V.6; P. 15-16; L1. 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- 
