of Poeciliid Fishes. 505 



a little deeper than broad. Diameter of eye 3 in the length 

 of head. 30 scales in a longitudinal series. Dorsal 9 ; 

 origin in advance of middle of anal, twice as distant from 

 eye as from base of caudal. Anal 14, ending below last 2 or 

 3 rays of dorsal. Pectoral | the length of head, extending 

 beyond hase of pelvics, which extend beyond origin of anal. 

 Brownish, with a darker spot on each scale of upper part of 

 sides ; dorsal and anal barred ; caudal dusky. 

 Colombia. 



1 (type). 45 mm. Colombia. Wolterstorff; 



Pterolebias. 



Garman, Mem. Mus. Comp. Zool. xix. 1897, p. 141. 



This genus appears to differ from Rivulus in the deep, 

 strongly compressed tail, with sharp lower edge, and in the 

 elongate fin-rays, the pelvics extending to the posterior end 

 of the anal. 



1. Pterolebias longipinnis. 



Pterolebias longipinnis, Garman, Mem. Mus. Comp. Zool. xix. 1897, 

 p. 142. 



Dorsal 9-10. Anal 19-20. 31 or 32 scales in a longitu- 

 dinal series. Brownish ; fins spotted. 

 Santarem. 

 Total length 80 mm. 



Cynolebias. 



Steind. Sitzungsb. Akad. Wien, Ixxiv. 1876, p. 172. 



This genus differs from Rivulus in the subequal many- 

 rayed dorsal and anal fins ; the species are deeper and more 

 compressed than most of the Rivuli. 



Synopsis of the Species. 



I. Pectoral fin not extending beyond origin of anal, which is nearly 

 below that of the dorsal, nearer to base of caudal fin than to end 

 of snout. 



A. Pelvics not reaching anal. 



28 scales in a longitudinal series. D. 16-18. A. 17-20. \. melanotcenia. 

 45 to 50 scales in a longitudinal series. D. 17. A. 20. 2. elongatus. 



B. Pelvics extending beyond origin of anal ; 28 to 30 scales in a 



longitudinal series. D. 17-19. A. 22-26. . . . 3. maculatus. 



