NATURAL SCIENCES OF PIIILADELPEIA. 185 



which has not beeu noticed in descriptions. In the collection of the Aca- 

 demy. 



Helix ccltellatus, Thomson, MSS. Testa orbiculato-depressa, nitens, cari- 

 nata, corneo-rufcscens, ad peripheriam et ad suturas albo-zonata; anfr. 6i 

 convexiusciili, striis miuutis increnient:ilibu3 et lineis microscopicis spiralibus 

 decussati; sutura impressa, apertura oblique lunaris ; pcrist. simplex, acutum, 

 ad coluraellam vix reflexiusculura ; siibtus hcvigata, albida, infra carinani late 

 rufo-corneo-zonata ; umbilicus perspectivus, anfr. omnes ad apiceni monstrans. 

 Diam. maj. 35, min. 19, alt. 13 mill. 



Habitat. " Contra Costa Co., California." J. H. Thomson. 



Animal iwice the length of the diameter of the shell ; color reddish. 



Mr. J. H. Thompson, of New Bedford, Mass., proposes this name for a shell 

 found by him living in considerable quantities. The circumstances in which 

 it was discovered are very unfavorable to the supposition of its having been 

 brought from abroad. The chances of a Dalmatian shell having been intro- 

 duced into California, and already multiplying there, are very small indeed. At 

 the same time the shell before me bears strong resemblance to the European 

 group of this type. It seems to be between H. albanica, Ziegler, and acies, 

 Partsch ; the carina be.ng less sharp than in the latter. Mr. Thomson suggests 

 that it may have been imported from the Sandwich Islands on vegetables, but 

 there is no species native to that region which bear any resemblance to this. 



Helix anacooketa. T. orbiculato-convexa, aperte umbilicata, cinereo- 

 rufescens, granulata et rare indenta; spira elevata, conica; anf. 6 convex!, 

 ultimns subtus ventricosus ; sutura impressa ; perist. incrassatum, vix reHexius- 

 culum, violaceo-albidum, umbilicum hand multum occultans, marginibus ap- 

 proximatis, callo conjunctis ; faux violacea ; apertura obliqua, transverso- 

 rotundata. Diam. maj. 26 ; min. 21 : alt. 14 mill. 



Habitat omniam Californian. J. H. Thomson. 



Shell reddish ashen, orbicularly convex ; spire elevated, conic ; umbilicus 

 open, slightly concealed by the peristome ; whorls six, granulated and sparsely 

 indented ; suture impressed ; below ventricose; aperture transversely rounded; 

 peristome thickened, scarcely reflected, whitish, with a violet tinge, the ex- 

 tremities approaching each other and tbnnected with a callous on the parietal 

 wall ; throat violet. 



" Animal light ashen color, tentacles nearly white ; average length of some 

 thirty specimens 2Mnches (2 diameters of shell); superior tentacles 5-8ths; inferior 

 .T-lGths inch ; foot broad at the posterior extremity; a line of large granules 

 down the jpiddle of the back ; sides of foot margined with a line of light 

 granules (pores) ; genital orifice posterior to and beneath the larger tentacles. 

 In its habits solitary." Thomson. 



It with some hesitation that I propose a name for this shell. I at first con- 

 sidered is as a bandless variety of Californicnsis, Lea. But on expressing this 

 opinion to Mr. Thompson, he gave me the above description of the animal and its 

 habits, which are quite distinct from those of Mr. Lea's shell. Its characteris- 

 tics were found constant at various remote points of the State, and in a con- 

 siderable number of specimens. They seem too great for a simple variety. 

 The animal is also different in its habits from Californiensis, being found only 

 solitary, while the latter is gregarious. 



The shell is one of the very few bandless species of California. 



Helix .eruginosa, Gould. (Proc. Boston Soc. N. H., Feb., 1855, p. 137.) 

 Nomen transmutandum est ob. H. jeruginosam, Pf. (Pro. Zool. Soc, London, 

 1854.) This name being preoccupied for a Philippine Island shell. Dr. Gould 

 proposes to call it H. arkosa. " Inhabits only Redwoods." (Thompson). It 

 seems a very variable shell. The type resembles in shape JI. Toivscndiana, Lea. 

 Among the land shells collected in California by Dr. J. S. Newberry, P. R. R. 

 Survey, was one which I called var. /3 of Dr. Gould's shell. It has a very 

 elevated, conical spire, like elevata, Say, but agrees in other respects with tile 

 1857.] 



