HELIX. 



and move "with great rapidity, often entering and 

 coming out of the respiratory foramen. Their presence 

 does not seem to cause any uneasiness, nor even to be 

 felt by the snail. 1 



5. HELIX CLAUSA. 



PLATE IV. 



H. testa sub-globosa, sub-imperforata, luteo-cornea ; an- 

 fractibus striatis, striis minutis, crebris ; apertura rotun- 

 data ; peristomute albo, margine reflexo. 



SYNONYMS AND EEFEEENCES. 



Helix clausa, SAY, Jour. Acad. II. 154. 



American Conch. No. 4. pi. 37, f. 1. 



BINNEY, Boston Jour. Nat. Hist. I. 482, pi. 15. 



KIRTLAND, Ohio Report, 112. 



SAGER, Michigan Catalogue, 14. 



DE KAY, New York Report, 31. 



Helix MitcheUiana, Lea, Am. Phil. Trans, vi. 87, pi. 23, f. 71. 

 Helix Mitchella, Kirtlaud, loc. cit. 173. 



DESCRIPTION; 



ANIMAL. Blackish. 



SHELL. Rounded, or somewhat globular; epidermis 

 light yellowish brown or russet color; suture distinct; 



1 Ilypopus concolor, HALDEMAN. Oval, nearly colorless 

 or very pale ochraceous ; bristled ; sides impressed. 

 Length, 0.4 millim. 



Differs in outline from the European species, which it 

 resembles in general appearance, mode of life, and in the 

 large pair of projecting setae anteriorly and posteriorly. A 

 colored dorsal line has been observed. 



