41G 



7. Viviparid Snail of unusual tolerance. 



Campeloma suhsolidmn Anthony. This species was taken in upper 

 Peoria Lake in 1922 ; and in the river as far north as Starved Rock in 

 1912, which was at that time sHghtly above the lower limit of the 

 Sohaerotikis zone. 



Group II 



CLEANER PREFERENCE SPECIES; BUT SEE QUALIFICATIONS BELOW 



Though these species are clearly to be grouped as cleaner-preference • 

 forms by comparison with those included in Group I preceding, as com- 

 pared with the assemblage of species wholly exterminated in Peoria Lake 

 and the Illinois River to a point below Havana shortly before 1920 even 

 they may be judged to possess a measurable, if rather slight, degree of 

 tolerance. They are for the most part, both in Peoria Lake and elsewhere, 

 however, confined either to locations very near shore; to the swifter water 

 sections, as the narrows of the lake, or shortly below dams; or to the 

 southwest comer of middle Peoria Lake, just above Peoria Narrows (see 

 p. 17, and foot-note thereto). 



1. Mussels (Unionidae) 



Lampsllis pawns Barnes. S. W. portion of middle lake and 



Peoria Narrows. 

 Lampsilis gracilis Barnes, young. Wesley, shore-zone in good 



current. 

 Lampsilis species, young. Wesley and Seven Mile Island, in 



current. 

 Plaqiola donaciformis Lea. Quiver Beach, more probably from 



the lake than the river hauls. Label does not distinguish. 



2. Snails. (Valvatidae and Pleuroceridae) 



Valvata bicarinata Lea. W. beach, Rome. 



Valvata tricarinata (Say). W. beach,' Rome: also taken in same 

 location summer 1922. 



Valvata bicarinata var. normalis \\'alker. Shore zone, Mossville ; 

 channe, Al Fresco Parkl 



Gouiobasis livcsccns Mcnke. Channel. Peoria Narrows and 

 McKinley Bridge, in strong current. 



Plciiroccra clcvatum var. Ici^^isii. Channel, Peoria Narrows, Mc- 

 Kinley Bridge, and Pckin, in strong current. 



3. Sponges (Porifera) 



One or more species taken. Channel at Peoria Xerrows and 

 Pekin, in strong current. 



4. Fresh-water Hydroids. (Hydrozoa) 



Cordxlophora lacuslris .Mlman. Kingston Ferry near shore. 



