the; ILLINOIAN ICE INVASION 307 



Posey County, % mile south of New Harmony. 



Zonitoides arborea Polygyra monodon 



Euconulus fidvus \ Succinea lineata (= grosvenori) 



Strobilops labyrintkica Helicina occulta 



Polygyra hirsute Pomaliopsis lapidaria 



One mile southeast of Kilroy. 

 Polygyra elevate Circinaria concaia 



thyroides Succinea lineata ( = grosvenori) 



Three-fourths mile southwest of Stewartsville. 

 Zonitoides arborea Polygyra hirsute 



Euconulus fuhus " thyroides 



Strobilops labyrinthica Succinea lineata ( = grosvenori) 



Helicodiscus lineaius(= parallelus) Galba humilis modicella 



Other localities in Posey County are, 2 miles north of Grafton and 1 mile 

 southwest of Poseyville. One mile west of Mounts, Gibson County, a deposit 

 occurs which must have been formed in water as the shells are all aquatic. 

 This was probably a pond or stream which later was partly drained and finally 

 filled with loess. Six species have been identified, as noted below: 



Galba humilis modicella Valvata tricarinata 



Planorbis parvus Pisidium variabile 



bicarinatus ( — antrosus) " compressum 



Near Mt. Carmel and Keensburg, in Wabash County, Illinois, loess fossils 

 were also found. From two of the best known Indiana localities, New Har- 

 mony and Grand Chain, Daniels collected 26 species. The loess is here cov- 

 ered with two feet of soil; the shells occur from 6 to 15 feet below the surface, 

 being more plentiful from the middle to the bottom of the deposit. Polygyra 

 monodon is abundant in the loess, but no living specimens occur here or else- 

 where in the state except on the marshes bordering several of the lakes in the 

 northern part of the state, where it is abundant. 105 The species noted by 

 Daniels are listed below. 106 



x Helicina occidta Vitrea hammonis 



Vallonia pulchella " whealleyi 



Polygyra multilineata Euconulus fidvus 



x " hirsute Zonitoides nitida 



x " monodon " arborea 



x fralerna Gastrodonta ligera 



Strobilops labyrinthica Pyramidula alternate 

 " ajjinis " perspectiva 



Pupoides marginatus " cronkhilei anthonyi 



Bifidaria armijera Helicodiscus parellelus 



105 Daniels, Nautilus, XIX, p. 62. 



106 Op. cit., p. 63; x indicates abundant. 



