92 



sub-pelluclda ; fusco-cincta ; supra sub-discoidea, infra cinctura 

 rapida decliva ; perissimplex breviter expansa ; columella et fauces 

 purpureo-tinctffi. Diam. 26 mill. 



Axis. 16 " 



Shell verj near to H. Dupetit Thouarsi Desk, but differs in the 

 last whorl not dcscendin*; above, less thickened lip, in having 

 numerous microscopical interwoven stride. Shell pale corneous, 

 somewhat pellucid, brown-banded ; sub-planulate above, (or but 

 little elevated) below the band shelving down rapidly ; lip simple, 

 scarcely expanded ; columella and fauces tinged with purple. 



Hab. Los Angeles, Cal. 



Remarks. — To distinguish this from its nearly allied species, we 

 may again notice the minutely impressed, revolving and somewhat 

 undulating strii^, giving the shell under the glass a texturate ap- 

 pearance. 



The absence of the deflection of the outer lip found in all speci- 

 mens of the Dupetit Thouarsi, and the want of the dark color in 

 this species, will be sufficient to enable us to distinguish them at a 

 glance. 



No apology is required for my associating the name of Dr. Trask 

 with this beautiful species. 



Vitrina Pfeifferi. — V. testa sub-depr(issa, laevigata, nitida, pel- 

 lucida, virenti albida ; anfr. 3, ultimus permagnis ; sutura sub- 

 tillissima marginata ; apertura ampla, obliqua rotundato-ovata ; 

 peristenue; columella arcuata. Diam. 5 mill. 



Axis. 2 " 



Shell moderately depressed, smooth, shining pellucid, greenish 

 white ; whorls 3, the last composing most of the shell ; suture very 

 finely margined ; aperture large, obliquely and roundly ovate ; lip 

 thin, columella arched. 



Hab. Carson A'' alley. 



Remarks. — This species, about the size of V. diapliana, (Drap.) 

 but much more rounded, can be confounded only with the follow- 

 ing, viz : V. angelicce (Beck) from Greenland, which has " an- 

 fractus maximus verticaliter plures strias subfiles subeminentes ; ad 

 suturam notabiliores," not applicable to this species ;. with V. 

 limpida (Gould) [^Americana Pfr.] which is smaller, with a lighter 

 texture and two and one-half whorls only ; finally, with V. mexicana 

 (Beck) of which I can find no description. Dr. Pfeiffer in his 

 great work, " Mon. Ilel. Viv." vol. 4, part 2, page 798, refers back 

 to vol. 2, page 510, where the following observation occurs : 

 " Praeterea nulla Vitrinarum genuinarum species ex America mihi 

 innotuit excepta V. mexicana (Beck) [ined]." 



The probability is, that V. mexicana is from Southern Mexico, 

 consequently, from a tropical region, and from a distinct zoological 

 province. 



