IIKLIX.— I'LATE CXVIl. 



(){ the saiiiL- type as the preceiliui^ species, hut having 

 the periphery produced throughout into a sharj) prominent 

 keel. 



Species 684. (Mus. Cuming.) 



Hki.i.v Baskekvii,lei. Hel. testa umbilicatd, yloboitu- 

 depreaad, nolidiiuculii, iubpellucidd, oitit/ui plicato-ru- 

 ifiilosd, lineis ^piralibwi impremui minuti decussatA, 

 olivacto-fmcd ; ipird aubconoided ; anfractUjiui snx, an- 

 (jtislU, cunveximculk, ultimo rntundalo, antici cix de- 

 scendente ; aperturd oblique lunari, dente linguifornii 

 ttlbo pariete aperturali ; perintoniate late incramato, 

 carneo-albido, manjiite bnsali appresau, Hubdenlato, ca- 

 lumellari dilatato, callosu, umbilicum nemilegeiitt:. 



Baskerville's Helix. Shell umbilicatcd, globoselj de- 

 pressed, rather solid, subtranspareut, obliquely pli- 



cately wrinkled, minutely decussated with impressed 

 spiral lines, olive-bruwn ; spire subconical ; whorls 

 six, narrow, rather e<jiivex, the last rounded, but 

 little deseeniiing in front ; a|)crturf obliquely hinur, 

 with a white tongue-8ha|)ed tooth on the wall of the 

 aperture ; lip broadly thickened, flesh-white, basal 

 margin appressed, slightly toothrd, columellar <lilal<-d 

 and callous, half-covering the umbihcus. 



Pfeifkek, Pro. Zool. Soc. 1«49, p. 130. 



Ilai. Vancouver's Island : Lieut. Baskenrillc. 



This species firom Vancouver's Island presents the 

 same trifting but characteristic departure from the North 

 American t\^e as the //. Roeineri from Texas, namely, 

 that the regxUar rib-likes tria; arc rcplaci-d by irregular 

 plicately wrinkled striae. 



