Mollusca of Great Britain. | 357 
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. s. 3. 
Maton & Rackett in Linn. rsp 8. p. 182. 
a. major, fulva, feré edentula. 
Common everywhere among moss, in the clefts of old 
walls, &c. 
The character of “ apertura edentula” given by Linnzus 
to his Turbo muscorum will hardly suit this species. I rather 
think that celebrated naturalist has, with Geoffroy, Miiller, 
and others, confounded it with the following, to which, in- 
deed, at first sight it bears no slight resemblance. 
Genus VIII. ALAA. 
Animal ; tentaculis inferioribus punctiformibus. 
Testa verè cylindrica. Apertura extùs plerumque marginata, et 
.. intüs denticulis sive lamellis incontinuis munita, mar- 
ginibus subzqualibus: peristomio simplici. 
I have separated this from the genus Vertigo as esta- 
blished by Férussac, 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 MN. psal bees vti Bee 
T MaRa 
Animal nigro-griseum, nitidum. Sustentaculum crassulum. 
Testa subventricosa, nitida, glabriuscula, corneo-fuscescens. 
 Anfractus 
