100 



GEOIyOGY OF IvA SALLE COUNTY. 



Helix profunda, Say — Shell depressed, umbilicat- 

 ed, lip white, reflected, thickened, with a blunt callus 

 on the inner side near the base, w^hirls six, shell horn 

 color with two broad, revolving- bands and two small- 

 er ones, all of a reddish color, extending- into the aper- 

 ture; has coarse and oblique strise, umbilicus largx and 

 deep; g-reatest breadth one and one-fourth inches. 



Another of our banded species. Some have but 

 one band. A variety with a sort of porturberance on 

 the outer circumference of the last whirl, one-fourth 

 inch from the marg-in of the lip occurs. C. 



SUBGENUS STENOTREMA, RAF. 



Helix hirsuta. Say. — Shell has five rounded whirls 

 w^hich are covered with fine bristly hairs, resembling- 

 minute spines; aperture narrow, almost closed by an 

 elong-ated tooth on the parietal wall, peristome de- 

 pressed with notch near its center, umbillicus covered, 

 breadth 8}4 mill. 



Some of the finest specimens I have seen were 

 found by Mr. A. C. Baldwin and myself in the Deer 

 Park, and in a ravine on the south side of the Vermil- 

 lion River, near the Farm Ridg-e Bridg-e. The rich, 

 deep chestnut coloring- is noticeable. 



HELIX MONODON, RACKETT. 



Shell depressed, whirls five, hairy; umbillicus 

 partially covered, aperture lunar, a lanielliform tooth 

 on the parietal wall, peristome white, acute, reflected; 

 shell horn color, breadth 10 mill. 



Not so abundant as the preceding-, but has been 

 found by Mr. A. C. Baldwin and myself in the town 

 of Deer Park. Other places near the timber. The 

 situations were dry ones. 



Helix monodon, Rackett. — Variety Leaii, Ward — 

 A somewhat smaller shell than //. rnouodon, of which 



