87 



Family IV. SERRANID.E. (The Sea Bass.) 

 Genus 4. Roccus, Mitchill. 



Bass. 



4. Rocciis intsrruptus, Gill. — Yellow Bass; Steiped Bass; Brassy /V 



Bass. 



(Bui. II, 44 ; Morone interrupta.) 



This species has not occurred in Northern Illinois to our knowl- 

 edge, but has been collected by us almost wholly in the Illinois 

 River and in the bottom lakes connected with that stream. 



5. Roccus cliri/sops, Raf. — WnrrE Bass; Silver Bass. '- 



TLvoughout Illinois, in creeks and rivers, and in Lake Michigan, 

 much more rarely in the small northern lakes. It seems, indeed, 

 to be wholly wanting in the lakes of the Fox River system, in which 

 it is said by the older fishermen to have been exterminated by 

 severe winters some years ago. The presence of impassable fish- 

 dams in the Fox River, through which these lakes are drained, 

 probably accounts for its non-appearance since. 



Family V. PERCID^. 



Sub-family PERCiNiE. (The True Perches.) 

 Genus 5. Stizostedium, Raf. 



Pike Perches. 



6. Stizostedium canadense, Smith. — Sauger; Sand-Pike; Gray-Piice. 



The distribution of this species in Illinois is precisely like that of the 

 following. 



7. Stizostedium vlircum, Mitch.. — Wall-eyed Pike ; Dory ; Glass-eye ; i 



Yellow Pike; Blue Pike; "Jack Salmon." 



Found only in the larger rivers and lakes ; occurring in our col- 

 lections from the Wabash, Illinois, and Rock Rivers. Especially 

 abundant in the former at the rapids above Mt. Carmel. 



Genus 6 Perca, Linnteus. 

 Perch. 



8. Perca americckiia, Schranck. — Yellow Perch; American Perch; - 



Ringed Perch. 



A very abundant species in the northern part of the State ; ex- 

 cessively common in Lake Michigan, where it is caught from the 

 wharves by thousands daily. Also swarming m the small northern 

 lakes, and one of the commonest fishes in tlie clearer creeks and 

 rivers. In Central Illinois it is somewhat rare, occasional speci- 

 mens only occurring in the Illinois. In the southern part of the 

 State we have not seen it at all, not a single specimen, in fact, 



