14. GAMBirsiA. 335 



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

 thirds. Snout broad, subspatulate, with the lower jaw projecting 

 beyond the upper. The diameter of the eye is somewhat more than 

 the length of the snout, one-third of that of the head, and two-tliirds 

 of the width of the interorbital space. In the female the origin of 

 the dorsal fin is midway between the extremity of the caudal and the 

 front margin of the orbit, and opposite to the seventh anal ray. In 

 the male the origin of that fin is in the middle of the total length. 

 Anal process of the male longer than the head, not curved at its ex- 

 tremity. Pectoral fins reaching nearly as far back as the ventrals, 

 which terminate immediately in front of the anal fin. Free portion 

 of the tail rather elongate, the length of the base of the anal fin of 

 the female being conspicuously less than one-half of its distance from 

 the caudal fin. A faint dark line runs from the superciliary, above 

 the opercle, along the upper half of the trunk. Frequently a series 

 of black dots, and sometimes other dots irregularly scattered, on the 

 side of the body. Two or three transverse bands of dots on the 

 dorsal and caudal fins. An oblique brownish band below the orbit. 

 Frequently uniform brownish olive. 

 Southern States of North America. 



a. Many female specimens, 1| or 2 inches long. New Orleans. 



b. Many male specimens, 1 or 1^ inches long. United States. From 



Mr. Parnell's Collection. 



c. d. Many female specimens, 1^ or 2 inches long. United States. 



From Mr. ParneU's Collection. 

 e. Adult female. North America. Presentedby E. Doubleday, Esq. 



4. Gambusia humilis. 



Gambusia gracilis, Girard, Proc. Acad. Nat. Sc. Philad. 1859, p. 121 

 (not Heckel). 



D. 6. A. 9. V. 6. 

 Body slender ; the length of the head a little more than one-fifth 

 of the total (with the caudal). Caudal rounded; anal larger than 

 dorsal, its end being nearly opposite to the origin of the dorsal. 

 Ventrals extending nearly to the anal ; pectorals beyond the base of 

 the ventrals. Olive-brown, dorsal and caudal with narrow blackish 

 cross bars. (Girard.) 

 Matamoras. 



5. Gambusia uobilis. 



Heterandria nobilis, Baird Sf Girard, Proc. Acad. Nat. Sc. Philad. 



1853, p. 390. 

 Gambusia nobilis, Girard, IT. S. ^ Mex. Pound. Ichthyol. p. 71, pi. 39. 



figs. 8-11, and Proc. Acad. Nat. Sc. Philad. 1859, p. 120. 



D. 8. A. 7. V. 6*. 

 The height of the body is contained thrice and one-third in the 

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

 half. Origin of the dorsal fin in the middle of the total length. 

 * D. 9. A. 8, according to the figure. 



