200 PNEUMONOBRANCHIATA. 



Turbo muscorum var. Montagu, T. B. 356. 

 Jaminia edentula. Risso, iv. 89. 

 Alasa revoluta. Jeffreys, Linn. Trans, xvi. 515. 558. 

 Turbo edentulus. Wood, Cat. Suppl. t. 6. f. 14. 

 Var. Shell more elongated and cylindrical. 



Marshy places, at the roots of grass, under stones 

 and on trees. 



Animal grey ; upper tentacles clavate. 



Shell the tenth of an inch long, horn-colour, trans- 

 parent, slightly striate ; spire composed of five or six 

 rounded and deeply divided volutions ; aperture with a 

 very thin margin, without the rib behind the outer lip. 



The young shells are very transparent light horn- 

 colour, and brittle ; the apex of the adult shell is often 

 whitish and slightly eroded. 



Montagu was acquainted with this shell, but had 

 not fixed it as a distinct species. 



It is very probable that this is the true Turbo mus- 

 corum of Linnaeus, as it most accurately answers his 

 definition in the Sy sterna Natures. " Testa ovata 

 obtusa pellucida, anfractibus senis secundis, apertura 

 edentula." 



Mr. Jeffreys, in his Supplement, observes, " The 

 Alaia revoluta of his Synopsis is an old bleached spe- 

 cimen, with the aperture placed more extrinsecall} 

 than usual." {Linn. Trans, xvi. 515.) 



70. 2. Vertigo cylindrica. Cylindrical Whorl Shell, 

 (t. 140. f. 10.) Shell attenuated, pellucid, pale 

 brown, acutely obliquely striated ; whorls five, 

 convex; mouth ovate, slightly margined exter- 

 nally, toothless; umbilicus narrow. 

 Pupa obtusa. Flem. Brit. Anim. 269. ; not Drap. 



