167 



alternata in form ; but in its opaque and rugged aspect, and in 

 most of its characters, it nearly resembles H. alpina of Europe. 



Helix sportella. Testa planulata, fragilis, nitida, luteo-cor- 

 nea, subtus concava, late umbilicata, lineis incrementi conspicuis 

 et lineis volventibus subtilissimis confertim decussata : anfr. ^, 

 ultimo magno ; sutura profunda : apertura rotundata, infra suban- 

 gulata ; labro acuto, simplici. Lat. ^, alt. |-^ poll. Hah. Puget 

 Sound, Oregon. 



Much like H. concava, but has a smaller umbilicus, and larger 

 aperture, and the transverse incisions of the strise are sufficiently- 

 distinctive. 



Helix mutata. T. orbicularis, depressa, tenuis, cerina, infra 

 rotundata : spira anfr. 4 convexis, nitidis, junioribus glabralis, 

 majoribus supra crassi-striatis, subangulatis ; sutura impressa : 

 subtus glabra, sulcis radiantibus remotis radiatim divisa, umbilico 

 modico perforata ; apertura ampla, lunata, basi subangulata ; 

 labro simplici. Lat. ^^q, alt. ^q. Hah. Rio Janeiro. 



Not unlike H. alliaria, or small specimens of H. cellaria, in 

 general aspect ; but it is more globose and coarsely rib-striate, 

 like H. Pennsylvanica. It may be H. insignis, D'Orb. 



Helix lyrata (Couthguy MS.). Testa minuta, depressa, 

 rufo-cornea, umbilicata : spira anfr. 4 cylindricis, et striis elevatis 

 conferlis lyratis ; sutura canaliculata : apertura circularis ; labro 

 simplici. Lat. -^, alt. ^V poll. Hah. Terra del Fuego. 



About the size and color of H. rupestris^ but more depressed, 

 and with a less expanded umbilicus. It may be H. costellata, 

 D'Orb. 



A paper was connmunicated by Prof. James Hall, on the 

 geological relations of the fossil cranium mentioned on a 

 preceding page, and called Castoroides Ohioensis. 



The cranium was received from Rev. Benjamin Hall, D. D., 

 President of Geneva College, and was discovered in a swamp 

 on the farm of Gen. W. H. Adams, of Clyde. The situation in 

 which it was found is an elevated plateau or level tract of land, a 

 portion only of which would be denominated a swamp, though 

 the whole surface is covered with a peaty soil which supports a 



