70 
Genus 20. CrntTrarcHuus, C. & Y. 
43. Centrarchus macropterus, Lac. 
(Bul. II, 47; Centrarchus irideus.) i 
This is also a species confined in Illinois to the southern part of 
the State, where we have taken it in Cache River, in Clear and 
Drury Creeks, in Great House Creek near Mt. Carmel, and in various 
ponds and sloughs in the river bottoms of that region. 
Family VI. ELASSOMATIDAL. 
Genus 21. Enassoma, Jordan. 
44, Hlassoma zonatum, Jordan. 
A southern species, not collected by us north of St. Francisville, 
in Lawrence county. Not uncommon in small, muddy pools. 
Family VII. APHREDODERIDA. 
Genus 22. ApHreEDopDERUS, Le Sueur. 
45. Aphredoderus sayanus, Gilliams.—Pirate PERcH. 
(Bul. II, 48; Aphododerus isolepis.) 
Throughout the State from the Calumet to Union county and the 
Wabash, but far the most abundant southward. Occurs almost in- 
variably in small streams only, but occasionally taken in the Illinois. 
One of the commonest species in mud holes in the Mississippi bot- 
toms, in Southern Illinois. Very rare in the central prairie region. 
Family VIII. ATHERINIDA. (THE SILversIves.) 
Genus 23. LapnipEsTHES, Cope. 
4 
46. Labidesthes sicculus, Cope.—Brook SILVERSIDE. 
A very abundant minnow in small streams and lakes in Central 
and Northern Illinois; also occurs rarely in the Wabash Valley, 
commonly in Rock River, and occasionally in the Illinois. 3 
Order Il. HEMIBRANCHII. 
Family IX. GASTEROSTEIDAS. (THe StickLEBacks.) 
Genus 24. GastERosteus, L. 
47. Gasterosteus inconstans, Kirt.—Brook STICKLEBACK. 
Locally common in rivers and small streams in the northern part 
of the State only. We have not taken it south of Rock River. 
