268 Field Museum of Natural History — Zoology, Vol. VII. 



jj. Head longer, 4 in length of body; body deeper, ^-4, in length. 



rubrifrons, 274 



aa. Scales smaller; 40 to 50 in the lateral series, more than 20 scales 



in series between nape and origin of dorsal. umhratilis, 274 



Notropis anogenus Forbes. Least Minnow. 



Head 4.3 to 4.5; depth 4.3 to 4.5; D. 8; A. 7 ; scales 34 to 37. 



Body elongate, slightly compressed; head small; mouth very 

 small and very oblique, its gape making an angle of 20° to 30° with 

 the vertical; maxillary not reaching back of posterior nostril, its 

 length 4.5 to 5.1 in head; snout 4.5 to 4.8; diameter of eye 3.1 to ^.t^; 

 teeth 4-4 with well developed grinding surface, more or less hooked; 

 dorsal fin slightly behind ventrals, a little hearer base of caudal than 

 tip of snout; alimentary canal 1.2 to 1.3 times length of body; peri- 





FiG. 32. Least Minnow. 



Notropis anogenus Forbes. (After Forbes and Richardson.) 



toneum dusky; lateral line complete or nearly so; scales not smaller 

 on anterior portion of body, about 13 or 14 before dorsal fin. 



Color dark olivaceous above, silvery below; sides with a dark 

 lateral band, ending in a caudal spot; tip of lower jaw black. 



Length about i/i inches. 



A small species, 2 or 3 inches in length, ranging from Iowa to New 

 York. 



Fox River, McHenry, Illinois; Hickory Creek, New Lenox, Illinois. 



Notropis heterodon (Cope). Black-striped Minnow. 



Head 3.9 to 4.2; depth 4.1 to 4.6; D. 8; A. 7 or 8; scales 35 to 38. 



Body elongate, moderately compressed; head small, conic; mouth 

 terminal, obHque, its gape making an angle of 40° to 60° with vertical, 

 the tip of upper jaw on level with upper margin of the pupil; max- 

 illary scarcely reaching front of orbit; its length 3.6 to 4.0 in head; 

 snout pointed, 3.5 to 3.8; diameter of eye 2.7 to 3.0; teeth i or o, 

 4-4, I or o, the first three hooked and with grinding surface; ali- 

 mentary canal shorter than the body; peritoneum silvery; dorsal 



