G4 THE CYPRINODONTS. 



B. 5 ; D. 10-9 ; A. 10-9 ; V. 6 ; P. 16 ; LI. 29-31 ; Ltr. 9 ; Vert. 16 + 17. 



Depressed and wedge-shajied auteriorly, compressed behind the pectorals, 

 depth greater than length of head ; caudal pudicel deep. Head broader 

 than deep, narrowing forward and below, slightly arched across the crown, 

 one fourth or less of the length to the base of the caudal. Snout as long as 

 eye, broad, subtruncate, wedge-shaped as seen from the side. Mouth wide, 

 directed upward ; jaws weak, loosely joined, lower longer, upper shorter, 

 protractile. Teeth slender in the outer series, movable, narrowed at the 

 bases, broader and oar-shaped toward the apices, hooked ; inner teeth in a 

 band, very small, one cusped or with slight indications of lateral cusps; 

 pharyngeal very slender, the series arranged in short rows of three to seven. 

 Eye large, about half of interorbital space, as long as snout, one fourth of 

 head. Dorsal origin little in advance of the middle of the total length, 

 slightly behind that of anal in females. Anal of male farther forward, 

 between the ventrals, second to fifth rays modified to form an intromittent 

 organ, not as long as the head, with a fleshy lobe below the apex. Ventrals 

 small, second ray elongate in males. Pectorals rather elongate, reaching 

 behind the bases of the ventrals. Caudal deep, median rays as long as the 

 head, posterior border forming a very blunt angle or rounded. Scales large. 

 Intestine long. 



Light yellowish to brownish or olivaceous, lighter below, silvery on cheeks 

 and flanks, edges of scales darker. With or without narrow vertical bands 

 of darker separated by spaces of similar width on the flanks, more distinct 

 posteriorly. Top of head darker, with a lighter spot in the centre. With or 

 without a darker vertebral line. Fins tipped with darker, or plain. Dorsal 

 in cases darker near the base. Caudal sometimes with faint indications of 

 transverse bands. Smaller specimens have transverse series of small spots, 

 on the interradial membi'anes, on dorsal and caudal, the spot at the bases of 

 the third and fourth rays of the dorsal being blackest. 



Females up to four and one half inches ; males much smaller. 



Panama. 



Poecilia amazonica sp. n. 



Plate IV. Fig. 9, teeth. 



B. 5 ; D. 6 ; A. 9-8 ; V. 6 ; P. 13 ; LI. 26-28 ; Ltr. 7-8 ; Vert. 15 + 15. 

 Closely allied to P. vii'ipara, but distinguished by a smaller dorsal and by 

 the position of the lateral spot, present on the young. Head one fourth of 



