154 NORTHERN FISHES 



GENUS Margariscns Cockerell 



NORTHERN PEARL DACE (Leather Back, Nachtrieb's Dace) 

 Margariscns margarita nachtriehi (Cox) 



This minnow has a rather heavy body, a short head, and a bhint 

 snout. It is dusky in color and has faint black lateral stripes. The lateral 

 line contains about 72 scales. The teeth are 2, 4 — 5, 2. 



The northern pearl dace ranges from the Rocky Mountains through 

 the Dakotas, INIinnesota, and Wisconsin, to Maine, and northward to 

 the tundra. Originally described from specimens obtained in Mille Lacs, 

 it is found to be common in lakes over most of central and north central 

 Minnesota. It is scarce in or absent from the northeastern and extreme 

 southern parts of Minnesota. It occurs also in bog streams and rarely 

 in small, clear, cool, rocky streams. Greene (1935) found it common 

 in northern and central Wisconsin. It has not been reported from the 

 tributaries of Lake Superior. 



GENUS Fjrille Jordan 



FINESCALE DACE (Bronze Minnow) 

 Pfrille neogaea (Cope) 



This species (Figure 24E) is a medium-sized, robust minnow with a 

 large, broad, blunt head. It is blackish bronze in color, with dark lateral 

 bands. The lower parts are crimson in spring males. There are more 

 than 80 scales in the lateral line. The teeth in the main row are typically 

 5 — 4, but sometimes 4 — 4 or 4 — 5 or 5 — 5. 



The finescale dace ranges westward through southern Canada to 

 Minnesota and southward through parts of the Great Lakes basin. Rel- 

 ict populations occur in the Black Hills and western Nebraska (Hubbs 

 and Lagler, 1941) . In Minnesota it has been found in Brule Lake and 

 several other waters in the Lake Superior drainage in Cook and St. 

 Louis counties. Greene (1935) reported this species from Wisconsin in 

 streams in the Great Lakes drainage and gives one record of occurrence 

 in the Mississippi drainage. 



GENUS Chrosomus Rafinesqiie 



SOUTHERN REDBELLY DACE 



Chrosomus erythrogaster Rafinesqiie 



The southern redbelly dace is a small, brownish-olive minnow with 

 black spots on the back, a blackish stripe along the sides from above the 

 eye to the tail, and another band below running through the eye and 

 ending in a black spot at the base of the caudal fin. The belly and the 



