Mollusca of Great Britain. S57 



Long. 0.14.— Diam. 0.075. 



Pupa umbilicata. Drap.Hist.des Moll. p.62. t.3.f.39, 



40. Lam. Hist, des Anim. sans Vert. 6. p. 111. 

 Turbo muscorum. Mont. Test. Brit. p. 335. t. 22./. 3. 

 Maton Sf Rackett in Linn. Trans. 8. p. 182. 

 a. major, fulva, fere edentula. 



Common everywhere among moss, in the clefts of old 

 walls, &c. 



The character of " apertura edentula" given by Linnaeus 

 to his Turbo muscorum will hardly suit this species. I rather 

 think that celebrated naturalist has, with GeoftVoy, Miiller, 

 and others, confounded it with the following, to which, in- 

 deed, at first sight it bears no slight resemblance. 



Genus VIII. AL^A. 



Animal; tentaculis inferior ihus punctiformibus. 



Testa verh cylindrica. Apertura extus plerumque marginata, et 

 intiis denticulis sive lamellis incontinuis munita, mar- 

 ginibus subaequalibus : peristomio simplici. 



I have separated this from the genus Vertigo as esta- 

 blished by Ferussac, for the reasons stated in my remarks 

 on Clausilia. From Pupa it differs in the shell being always 

 of a more cylindrical form, and in having the aperture gene- 

 rally thickened by an exterior rib, and never reflexed. The 

 teeth too, when present, are never laminar or continued on 

 the penultimate whorl. The animal agrees in most respects 

 with that of Vertigo. 



1. Marginata. 



^nzmo/ nigro-griseura, nitidum. Sustentaculum crassulum. 



Testa subventricosa, nitida, glabriuscula, corneo-fuscescens. 



-^ ■'- Anfractus 



