148 FISHES OF NORTH CAHOLINA. 



dark, with numerous pale spots; dorsal sometimes having a black spot posteriorly; anal and 

 ventrals yellow anteriorly. Female, plain brownish green, lighter below, sides sometimes 

 marked by about IS dark crossbars narrower than the interspaces. {heterodUus, irregular.) 



The range of this killi-fish is from Maine to Mexico. It frequents chiefly- 

 brackish waters, but is also found in fresh water (as in the Potomac at Washing- 

 ton). It is very partial to shallow muddy waters, and one of its conamon names 

 is mud-dabbler, in allusion to its mud-loving habit. Length, up to 6 inches. 

 The species is an important bait fish, and is extensively eaten by squeteague, 

 striped bass, and other fish, as well as by water birds. 



135. rUNDULUS DIAPHANUS (LeSueur). 

 Killi-fish; Spring Minnow. 



Hydrargyra diaphana LeSueur, Journal Academy of Natural Sciences Philadelphia, i, 130, 1817; Saratoga 

 Lake. 



Fundulus diapkanua, Smith, 1893a, 191, 195, 197: Pasquotank and Roanoke rivers and Edenton Bay, Smith, 

 Notes on Fishes of Lower Potomac River (Bulletin U, S. Fish Commission 1890), 65, pi. xix, 1892. Jor- 

 dan & Evermann, 1896, 645, pi. ciii, figs. 275, 275a. 



Fig. 53. Spring Minnow. Fundvlus diaphanus. Male. 



Diagnosis. — Form elongated, slender, posteriorly compressed, depth contained 4.5 times 

 in total length; head depressed, .25 to .4 total length; mouth nearly horizontal, on level with 

 pupil, lower jaw projecting, angle of mouth. half way between eye and tip of lower jaw; eye 

 large, contained 3.5 times in head, 1.5 times in interorbital space, 1.33 times in snout; scales 

 about 45 in lateral series and 15 in transverse; dorsal fin low, beginning considerably in advance 

 of anal and nearer base of caudal than snout, rays 13; anal fin anteriorly sheathed by oviduct, 

 short, higher than dorsal, rays 11; edge of caudal fin straight or sUghtly emarginate. Color: 

 Male, uniformly olivaceous, darkest above, about 20 silvery vertical bars rather narrower than 

 the interspaces, which are the color of the body; back may be dark-spotted; a dark purplish 

 spot on opercle opposite eye; dorsal fin usually plain, occasionally faintly mottled with black 

 and white spots; other fins plain. Female, body marked by 15 to 20 dark vertical bars, 

 much narrower and shorter than silvery bars in male, the interspaces lighter than in male. 

 (diaphanus, transparent.) 



The southern limit of the range of this species appears to be North Carolina, 

 whence it extends to Maine and the upper Mississippi, in rivers and lakes. It is 

 found coastwise in abundance, in salt and fresh water, although it is less of a 

 salt-water form than Fundulus heteroclitus, and often occurs in mountain brooks, 

 in springs, and in clear cold lakes. It is very abundant in the lower stretches of 

 the rivers debouching into Albemarle Sound; numerous small specimens (all 



