June, 1841.] 27 



of the United States. By S. S. Haldeman. 8vo. Philad. 

 1841. No. 2. From the Author. 



Stirpium rariorum minusque cognitarum in Sicilia sponte pro- 

 venientium descriptiones, nonnullis iconibus auctas. Auctore 

 Antonio Bivona Bomardi. 8vo. Panormi, 1813. From 

 Mr. Haldeman. 



Report on the Geological Survey of New York, for 1840. 



From Dr. L. C. Beck. 

 The Floral Magazine and Botanical Repository, 4to. Philad. 



Nos. 1, 2, 3 and 5. From Mr. W. P. Gibbons. 

 Catalogue of Shells, arranged according to the Lamarkian 



system, together with descriptions of new or rare species, 



contained in the collection of J. C. Jay, M. D. 4to. New 



York, 1839. 2 copies. From the Author. 



Illustrations of Ornithology. By Sir William Jardine, and 

 Prideaux John Selby. 3 vols. 4to. Edinburgh. Presented 

 by Messrs. Poulson, Hembell, Elwyn, Wetherill, Vaux, 

 Ashmead and Morton. 



Written Communications. Mr. J. S. Phillips read descrip- 

 tions of two new American species of the genus Helix : viz. 



Helix Bidentifera. Testa convexa, depressa, corneo-lutea ; regu- 

 lariter et tenuiter striata, striis longitudinalibus, obliquis ; umbi- 

 licata, apertura compressa ; labro subreflexo, duobus dentibus 

 albis, rotundis, parvulis, in margine inferiore, instructo. 



Shell much depressed, rather thin, epidermis yellowish horn colour 

 shining ; whorls six, rounded, with very numerous, raised, oblique 

 striae ; suture strongly impressed ; aperture compressed, con- 

 tracted by a groove behind the outer lip ; outer lip moderately 

 reflected ; within the edge of the aperture on the lower portion, 

 two fine rounded white teeth, one near the umbilicus, the other 

 nearly equidistant from the extremities of the outer lip ; umbili- 

 cus round, of moderate diameter, not encroached on by the outer 

 lip, well defined and deep ; base rounded, more convex than the 



