344 



Summary of Bottom Spkcies Lists. Upper Peoeia Lake. Summer 1922 

 3. changes from mid-channel outward into wide waters 



rrUMBER OF KINDS TAKEN 



Larvae. 



WORMS 



The tube- worms (Tubificidae) and other small annelids recorded 

 from upper Peoria Lake in 1922 included not less than five kinds, and 

 were, along with one of the unusually tolerant snails, the conspicuous 

 feature from the point of view of abundance, of the muds in all cross- 

 sections. Three of the species belonged to the genus Limnodrilus, 

 viz., L. Itoffnicistcri Claparede ; an imidentified species similar to L. 

 claf<arcdcianus Ratzel ; and a species believed by Professor Frank 

 Smith, who determined the specimens, to be new. The genus Tubifex. 

 usually thought of as the common one in septic or jxilluted muds, was 

 represented by a single species, referred with question, because of 

 slight differences, to the European Tnbifcx tiibifc.v (Miiller). The 



