4-4G 



Haliplidae: Pcltodytes 12-punctatus (Say), aduhs. 



P. cdentulus (Lee), adults rare. 

 Hydrophiliade : Bcrosus striatus (Say), adults. 

 Diptera. Chironomidae : Procladius sp., larvae. 



Chironomus sp., larvae, few. 

 The occurrence of Hcxagcnia and Sialis usually indicates a clean- 

 water fauna, though Sialis infiimata has been found to prefer trashy and 

 sometimes slightly foul places. 



Station 12. — Station made in the Salt Fork, one mile west of the 

 junction with Spoon River, July 23. The Fork here is deep but foul- 

 smelling. Masses of sludge lie about the bottom, giving it a mottled ap- 

 pearance. 



Odonata. Libellulidae : LibcUula puJcbcUa Dru. and Plathe- 



iiiis lydia (Dru.). .A-dult females were obser\^ed 

 ovipositing in the stream but no naiades were 

 found. 

 Hemiptera. Cori.xidae : common, all adults. 



Gerridae : Gcrris marginatus Say, adults. 

 Coleoptera. Dytiscidae : Laccophiliis proximus Say. adults. 



Haliplidae: Pcltodytcs is-punctafus (Say), adults. 

 Hydrophilidae : Bcrosus striatus Say. adults. 

 Diptera. Chironomidae: Chironomus- sp.. larvae abundant. 



Palponi\ia sp.. larvae common. 

 Sludge-worms. A very large species of Tubifcx occurs. 



Station /?. — Railroad Bridge west of St. Joseph. July 23. The 

 river here is of bad odor and the bottom blotched with small masses of 

 sludge. Small patches of duckweed (Lciniia) float on the stream-sur- 

 face. 



Ephemeridae : Callihactis sp., possibly fcrruginca 

 Walk., a few naiades. This is the most tolerant 

 May-fly known to the writer. 

 Aeschnidae : Anax Junius (Dru.), naiades. 

 Libellulidae: LibcUula pulchcUa Dru., naiades. 

 Mesoveliidae: Mcsovclia mnlsanti White, adults. 

 Dytiscidae: Laccophiliis proximus Say, adults. 

 Haliplidae: Pcltodytcs u-punctatus (Say), adults. 



P. cdentulus ( Lee), adults, few. 

 Hydrophilidae: Tropistcruus sp.. large larvae. 

 Enochrus ochraccus (Melsh.). adults. 

 Bcrosus striatus (Say), adults. 

 Diptera. Chironomidae: Palpoinyia sp., larvae common. 



Procladius sp., larvae, few. 

 Chironomus sp., larvae, abtmdant. 

 Sludge-worms, Tubifcx sp.. and blood-worms. Chironomus sp.. are 

 abundant in the shallow waters. 



Ephemerida. 



Odonata. 



Hemiptera. 

 Coleoptera. 



