154 FISHES OF ILLINOIS 



a faint and narrow dark vertebral streak; fins plain; forehead, opercles, and 

 predorsal region flushed with red in spring males. Head long, conic, pointed, 

 3.8 to 4.3 in length, its width 2.3 to 2.6 in its length; interorbital space little 

 convex, 3 to 3.6 in head; eye smaller than in the last species, 3.2 to 3.6 in 

 head in adults,^ in which it is distinctly less than the maxillary; nose 3 to 

 3.4 in head; mouth rather large, oblique, tip of upper lip almost at top of 

 pupil; maxillary distinctly longer than eye, 2.7 to 3.1 in head, reaching 

 vertical from front of orbit; jaws subequal; isthmus less than pupil. Teeth 

 2, 4-4, 2, the grinding surface slight and present on few teeth; intestine .8 

 to .9 of length of head and body; peritoneum dusted with coarse brown specks. 

 Dorsal fin with 8 rays (occasionally 7), set well behind ventrals, so that 

 distance from dorsal to caudal is 74 to 81 per cent, of that from muzzle to 

 dorsal; longest dorsal ray 1.3 to 1.5 in head; anal rays usually 10, sometimes 

 9 or 11; pectorals scarcely % to ventrals, 1.2 to 1.5 in head; ventrals usually 

 short of vent. Scales 6 (or 7), 36-40, 3; rows before dorsal 17 to 21; lateral 

 line decurved anteriorly. 



The rosy-faced minnow is a bright-colored species which 

 dehghts in the clear waters of rapid streams. It has been rare 

 in our work, occurring only in the Mississippi drainage of the 

 northern third of the state, in the tributaries of the Illinois, the 

 Rock, and the Mississippi, and only once from the main stream. 

 It is a species of northern distribution, ranging from the lower 

 St. Lawrence and Lake Champlain to the Lake of the Woods, 

 thence southward to the headwaters of the James, through the 

 Ohio Valley to the Alleghany River, and to the tributaries of 

 the Missouri in Kansas and Missouri. In Ohio it is reported by 

 Osburn as occasionally occurring in large schools over clean 

 gravelly places in ripples, the females ready to spawn during the 

 latter part of May — a date which agrees with our own observa- 

 tions in Illinois. The spring males have the head and fore part of 

 the body excessively^ tuberculate, and there are sometimes weak 

 tubercles on the same parts of the breeding females also. 



NOTROPIS UMBRATILIS ATRIPES (Jordan) 



BLACKFIN 

 (Pl.. p. 147; Map XLV) 



Jordan, 1878, Bull. 111. St. Lab. Nat. Hist., I. 2, 59, (Lythrurus atripes). 



J. & G., 197 (Minnilus atripes); M. V., 61 (umbratilis) ; J. & E., I, 300, also (?) 301 

 (umbratilis fasciolaris) ; N., 47 (Lythrurus diplaemius) ; J., 59 (Lythrurus 

 atripes and diplaemius) ; F., 76 (also macrolepidotus) and Bull. 111. St. Lab. Nat. 

 Hist., II. 2, 138 (macrolepidotus): L., 18 (umbratilis). 



Fishes with the dentition and the elongate anal fin of Notropis (e. g., 

 atherinoides and ruhrifrons), but with the form of body (deep and com- 

 pressed) of Cyprinella (e. g., N. whipplii) or Moniana (N. lutrensis); most 

 easily distinguished from the fishes of the first subgenus mentioned by the 



