72 



88. Notropis fretensis, Cope. 



(Bui. 11,57; Alburnops fretensis: Synop., 107; Cliola Jretensis: M. V., 

 29S; Hybopsis fretensis.) 



Very rare in Illinois; not; more than a single specimen among: all our 

 cyprinoids certainly belonging to this species. 



89. Notropis anogenus, Forbes. 



Thus far taken only in Fox river, at McHenry, Illinois. 



90. Notropis heterodon, Cope. 



Thus far taken only in Fox river, at McHenry, Illinois. 



(Bui. II, 02. Hemitremia heterodon: Synop., 163; do.) 



This is, within our limits, essentially a species of lakes and larger streams 

 in Northern Illinois, although the form with perfect lateral line has been col- 

 lected in small numbers from the southern extremity of the State. It is one 

 of the most abundant minnows in the small lakes, northward. It likewise in- 

 habits the Illinois river and the bottom lakes communicating with that 

 stream. 



Genus 48. Cliola, Girard. 

 Silver Fins. 



91. Cliola vigilax, B. & G. 



(Bui. II, 66; Alburnops tuditanus: Snyop., 165; Cliola tuditana.) 



Abundant in small streams throughout Illinois. Seems to have been usually 

 confounded with Pimephales notatus, to which it bears a strong general re- 

 semblance. 



Genus 49. Pimephales, Raf. 



Fat-heads. 



92 Pimephales notatus, Raf.— Blunt- NOSED Minnow. 



(Bui. II, 55 and 57; Hyborhynchus, notatus, Hgborhynchus surpercihosus : 

 Synop., 159 and 100; do.) 

 One of the commonest of our fishes; extremely abundant in the prairie 

 streams which characterize so large a part of Illinois. It chiefly affects, 

 however, gravelly spots in muddy streams. It is not common in rivers, but 

 is occasionally taken at the mouths of creeks. It has not been found by us in 

 ponds, but specimens were collected from the small lakes of Illinois. 



93. Pimephales promelas, R-At—FA'T-B.EAD; Black-HEADED Minxow. 



The distribution of this fish in the State is somewhat peculiar. The species 

 is altogether absent, as far as our collections indicate, from the prairie streams 

 of Central Illinois. It is not uncommon in small muddy creeks connected 

 with the larger rivers, and occurs occasionally in these latter streams them- 

 selves. We have not taken it in lakes or ponds or similar waters, neither 

 has it occurred to us in Illinois south of the latitude of Alton. 



Genus 50. Hybognathus, Agassiz. 



94. Hybognathus nuliilus, Forbes. 



(Bui. 11, 50; Albiirnoi)s nnbilKs; Synop., 167; Cliola nubila.) 

 This minnow has thus far been reported only from Illinois, and has oc- 

 curred in our collections only from the extreme northern part of the State — 

 from the Rock river and its tributaries. 



