LA SALLE COUNTY SPECIES. 



FAMII^Y HEI^ICID^. — SUBFAMILY VITRININ^. — C;ENUS 

 MACROCYCLIS — BECK. 



Macrocyclis Concava, Say — Shell flattened, whirls 

 five, umbilicus broad and deep, shell striate, horn 

 color, breadth one-half inch. They are fond of animal 

 food, and are active; the shell rt^sembles M. vancouv- 

 erensis. Lea not so large and differs in other re- 

 spects. C. 



Genus Z^onites, Montford — Zonites arboreus, say. 

 Shell thin and depressed, whirls four and a half, lip 

 acute, light horn color, one-fourth inch in diameter. R. 



Zonites viridulus, Menke — (Hy. electrina, Gould.) 

 Shell depressed, thin, whirls three and one-half, lip 

 simple, shell umbilicated. Dia. 5 mill. Loc. Fox and 

 Illinois River Valleys. 



Zonites fulva, Drap. — (Helix chersina, Say.) — 

 Shell thin, acute, lip whirls five, aperture transverse, 

 breadth four mill. Abundant. 



SUBFAMILY HELICINAB 



Helicodiscus, Morse, — Helix lineata. Say — Shell 

 flat, whirls four, lip acute, two pair of teeth within 

 aperture, horn-color, breadth four mill. Very abun- 

 dant. 



Genus patula, Halde. — Helix alternata,Say — Shell 

 has five whirls, peristome acute, umbilicus deep, shell 

 not much elevated, and variegated with numerous red- 



