538 Illinois State Laboratonj of Natural History. 



Nostoc: 2 Ictiobus cyprinella, Aug.; 1 Polyodon spathula, Aug. 

 Oscillaria : 1 Chrosomus erythrogaster, Sept.; 1 Ictiobus, yg. 

 Chroococcus : 1 Erimyzon sucetta, If in.; 1 yg. 



Dirt: 10 Dorosoma cepedianum, Apr., June, July, Oct.; 4, 

 2|-5i in., July, Oct.; 1 Clupea cbrysochloris, If in., June; 

 10 Notemigonus chrysoleucus, July, Aug., Sept.; 3 Hy- 

 bopsis biguttatus, Aug., Sept.; 2 Phenacobius mirabilis, 

 Sept., Oct.; 1 Notropis hudsonius. May; 1 N. heterodon, 

 Sept.: 8 Pimephales notatus, July, Aug., Sept., Oct.: 4 P. 

 proraelas, May, Aug.; 8 Hybognathus nuchalis. May, Aug., 

 Sept., Oct.; 3 Chrosomus erythrogaster, June, Sept.; 9 

 Campostoma anomalum, Aug., Sept.; 8 Moxostoma, June; 

 2 M. aureolum, June; 3 M. macrolepidotum, June, Sept.; 

 2, 2^2| in., Aug.; 1 Minytrema melanops, Sept.: 1 

 Erimyzon sucetta, July; 6 Carpiodes, Mar., Apr., July, 

 Oct.; 5 Ictiobus urus, Aug.; 1 I. cyprinella, Aug.; 1 

 Amiurus nebulosus, Sept. 



