HELIX. 129 



IG. HELIX THYROIDUS, SAY. 

 PLATE XI. 



H. testa orbiculato-convexa, sub-umbilicata,luteo-cornea ; 

 anfractibus tenuiter striatis, striis confertis, obliquis ; appen- 

 diculo dentiformi, obliquo, columelloe adnato ; peristomate 

 albo, margine reflexo. 



SYNONYMS AND REFERENCES. 



Helix thyroidus, SAY, Nich. Eacyc. (Amer. ed.) IV. 

 Journ. Acad. I. 123, II. 161. 

 American Conchology, No. 2, pi. 13. 



FERUSSAC, Hist. pi. 49, a. f. 4 ; pi. 50, a. f. 6. ? 



DESHAYES, Encyc. Meth. II. 230. 



LAMARCK, An. sans Vert. 2 ed. VIII. 114. 



SAGER, Michigan Catalogue, 14. 



BINNEY, Bost. Jour. Nat. Hist. I. 488, pi. 18. 



DE KAY, New York Report, 31. 



GOULD, Invertebrata, &c., 171, pi. 108. 



ADAMS, Molltisca, &c., 9. 

 Helix thyroides, PFEIFFER, Monog. Helic. Viv. I. 356. 



DESCRIPTION. 



ANIMAL. Color a dirty yellowish white, with a grayish 

 hue in some individuals, tentacles darker, eyes black, 

 base of foot dirty white ; foot rather narrow, terminated 

 posteriorly in an acute angle. Length equal to twice 

 the breadth of the shell. 



SHELL rounded, convex ; epidermis, of a uniform 

 yellowish brown or russet color ; whorls five, with fine, 

 parallel striae, running obliquely across them ; suture 

 distinctly impressed ; aperture rounded, contracted by 



VOL. II. \1 



