451 



Coleoptera. Gyrinidae: Dincntcs amcricamis Say, adults 



scarce. 

 Helmidae : Stcnchnis sp., larvae. 

 Diptera. Chirononiidae : Tanytarstts sp., larvae and cases. 



Caiiibanis and species of darters were common in the stream. 



Station 22. — Stony Creek, one-halt mile above its union with the 

 Salt Fork ; a check station, August 2,5. The stream here is small but 

 flowing in riffles. The fauna is strictly that of normally clean water, 

 though slightly different from that of the adjoining parts of the Salt 

 Fork. 



Hemiptera. Corixidac: unidentified. 



Genidae, Trcpnhatcs f^ictus ( 11. S.). adults abun- 

 dant. 

 Hydrometridae : Hydronictra martini Kirk., adults. 

 Coleoptera. Hali]:)lidae : Pcltodytcs i2-piinctatiis (Say), adults. 



Dryopidae: HcUchns lilhophihts (Germ,), adults 



abundant. 

 Helmidae : Stcnchnis sp., adults abundant. 

 Diptera. Tabanidae: Clirysops sp., larvae. 



Station .'?. Bridge south of Oakwood, Aug. 2!). The collections 

 made here show a large and varied fresh-water fauna. 



Plecoptera. Perlidae: Pcrla sp., half-grown naiades. 



Ephemerida. E]jhenieridae : Hcxagcnia biliiicata Say, naiades 

 abundant. 

 Polymitarcys albiis (.Say), naiades. 

 Cacnis sp., possibly diniinitta Wk., naiades. 

 Hcptagcnia sp., two species, naiades. 

 ■Chirotcnctcs alhomanicatns Ndm. 

 Baetis sp., naiades. 

 Odonata. Aeschnidae: Epiacschna hcros (Fabr.), naiades. 



Goniplius sp., burrowing species, naiades. 

 Libellulidae : Macromia sp., possibly ilUnoiensis 



Walsh, naiades of various sizes. 

 Agrionidac: Hetacrina amcricana (Fabr.), adults 



very abundant, ovipositing in water. 

 Coenagrionidae : linaUagnia sp., naiades common. 

 E. cxsidans Hag., adults connnon. 

 Hemiptera. Ncpidae: Kanatra amcricana (Mont.), adults. 



Gerridae: Trcpobates picttis (H. S.), adults and 

 nymphs. 

 Mctrobatcs hcspcrius Uhl., adults and nymphs. 

 Vcliidae : RhagorcHa obcsa Uhl., adults and 



nymj)hs. 

 Mcsoveliidac : Mesovelia mulsanti W h i t e, adults 

 and nymphs. 



