168 Notes on certain Terrestrial Mollusca. 



"with fluviatile species to C. M. Wheatley by Professor B. Sil- 

 liman, of Yale College, New Haven, to whom I dedicate the 

 species. 



Remarks. — This shell in general form may be compared with 

 S. Haydeni W. G. Binn., to which indeed it is closely allied, 



Fig. 15. 



S. Haydeni W. G. Binn. S. Hawkinsi Baird. 



but it is more attenuated, the last whorl less tumid and the 

 aperture more narrow. It is distinguishable from S. Hawhinsi 

 Baird, of Brit. Columbia, having one whorl less and a differ- 

 ently formed aperture. 



Succinea Sfretchiama, now sp. 



T. globoso-conica, tenuis, pellucida, nitida, striatula, virenti-cornea ; 

 spira brevis, obtusiuscula ; sutura profunda ; anfr. 3 convexi, ultimus 

 mflatus ; columella arcuata, leviter incrassata, recedens; apertura obliqua, 

 rotundato-ovalis ; perist. simplex, marginibus callo tenui junctis. 



Shell globose conic, thin, pellucid, shining, striatulate, green- 

 fiq. 16. ish horn colored ; spire short, rather obtuse ; suture 



fcA deep ; whorls 3, convex, the last roundly inflated ; 

 columella arcuate, slightly thickened, receding; 



S. Stretchiana . . 



Biand. aperture oblique, roundly oval ; perist. simple, 



with the margins joined by a thin callus. 



Long. 6£, diam. 5 mill ; Ap. 5 mill, longa, medio 4 lata ; 

 anfr. ult. 5£ mill, longus. 



Habitat. — Little Yalley, Washoe Co., Nevada, on the Eastern 

 Slope of the Sierra Nevada, 6500 feet above the sea. A number 



