Notes on the Molluscan Fauna of Northern Illinois. 325 



Pleurocera — (Raf) . 

 P. suhilare, Lea. P. lewisii, Lea. Both abundant. The latter 

 Avill probably prove to be a good species. 



Gon iobas is — (Lea) . 



GoH. Uvescens, Menke. Gon. depygls, Say. All other reported 

 species of Goniobasis from this section may be referred to one of the 

 above. 



ConcTiifera. 

 Family Cijcladidce — (W.) 



Genus Sphaerium. 



S. simile, Say. S. partumeimn, Say. S. occidentale, Pr. S. trans- 

 versnm, Say. 



Genus Pisidium — (Pfr.) 

 P. abditum, Pr. P. compressum, Pr. 



Family Unionidce. 



U. oesopus, Green. U. alatus, Say. U. anodontoides, Lea. U. 



cornutus, Bar. U. capax, Green. U. coccineics, Lea. U. crassidens, 



Lea. U. donaciformis, Lea. Do., var. zigzag. U. dorfeuillianus, Lea. 



U. elegans, Lea. U. ellipsis, Lea. U. ebeniis, Lea. IF. gracilus, Bar. 



IT. gibhosus, Bar. U. iris, Lea. U. luteolus, Lam. U. loevissimns. 



Lea. U. ligamentinus. Lam. IT. metanevrus, Raf. U. multiplicatus, 



Lea. U. monodontus, Say. IT. novi-eboraci. Lea. IT. occidens, Lea. 



IT. obliquus. Lam. U. orbicularis, Hild. XT. pushdosus, Lea. IT. 



piistulatns, Liea. IT. plicatus, hesneur. IT. parvus, 'Bar. IT. rectus, ham. 



IT. rubiginosiis, Lea. U. retusus, Lam. U. securis. Lea. IT. spatnlatus, 



Lea. U. solidus, Lea. IT. tuberadatus. Bar, IT. triangidaris. Bar. 



U. trigonus, Lea. IT. undulatus. Bar. IT. verrucosus, B;ir. 



Margaritana — (Schum) , 



M. complanata, Bar. M. confragosa, Lea. ]\I. rugosa, Bar. Jf. 

 marginata, Say. 31. deltoidea. Lea. 



Anodo7ita — Brug. 



A. edentula. Lea. A. ovata. Lea. A. ivibecillis. Say. A. corpulenta, 

 Cooper. A. suborbiculata, Say. A. grandis, Say. 



