344 CTPRINODO>'TIDiE. 



tin with obloMg black spots on the interradial membrane of the basal 

 half, with a broad whitish posterior marginal band, and narrow 

 black edge. 



The female has the dorsal only spotted with black. 



Mexico. Vera Cruz, 



tf-6, c-e. Males, 2 to 3 inches long. From M. Salle's Collection. 

 f-g. Females, 2 inches long. Vera Cruz. Purchased of Mr. Cuming. 



9. Pcecilia dovii. 

 ? Gambusia (?) plumbea, Troschd, in Miiller, Reise Mex. iii. p. 106. 

 Closely allied to P. sphenops, but with the snout shorter, and the 

 anal situated more backwards. 



D. 9. A. 8. L. lat. 26-29. L. transv. 9. 



The height of the body is contained thrice and two-fifths in the 

 total length (without caudal), the length of the head thrice and three- 

 fifths ; the width of the interorbital space is rather less than the 

 distance between the front margin of the eye and the gill-opening. 

 The diameter of the eye is somewhat more than the length of the 

 snout, two-sevenths of that of the head, and rather more than one- 

 half of the width of the interorbital space. The origin of the dorsal 

 fin is midway between the root of the caudal and the occiput, and 

 corresponds to the twelfth scale of the lateral line. Origin of the 

 anal opposite to the second or third ray of the dorsal (in the female). 

 Dorsal fin of moderate size, anal small ; caudal scaly in its basal 

 third. Tail compressed, rather high, its least depth being equal to 

 the length of the head, without snout. There are seven longitudinal 

 series of scales on each side of the tail. Lateral Hne rather indistinct. 

 Uniform brownish green on the head and body. 



The male has the dorsal fin slightly elevated, but the longest ray 

 is scarcely as long as the head, without snout ; this fin is ornamented 

 with small round black spots. Anal fin modified into an intromittent 

 organ, and advanced to between the ventrals and m front of the 

 dorsal. Tail strongly compressed, but not higher than in the female. 

 Caudal fin with minute black spots on the interradial membrane. 

 Back of the tail sometimes with indistinct narrow dark cross bars. 



The female has the fins coloured as the male. 



Guatemala; Mexico. 



a. Several male and female specimens : males 2 inches long, females 

 2| inches. Lake of Nicaragua. Presented by Captain Dow. 



h. Several specimens, from 2 to 2| inches long. Lake of Amatitlan. 

 From Mr. Salvin's Collection. 



c-d. Females, 3 inches long. Mexico. From M. Salle's Collection. 



Prof. Troschel informs me that his Gambusia (?) plumbea belongs 

 to this genus ; but it is uncertain whether it is specifically identical 

 with P. dovii. 



