VERTIGO. 165 



compressed, gradually increasing ; spire somewhat produced, 

 apex obtuse ; suttire deep ; inoiith narrow, horseshoe-shaped, 

 with strong contractions in the middle and near the base of the 

 outer edge ; teeth usually four to five, two on the base of the 

 penultimate whorl, one on the pillar, which is thick and fold- 

 like, and winds far within the shell, and a thick blunt tooth 

 (as well as sometimes a smaller one) on the inside of the outer 

 lip; outer lip very slightly inflected, remarkably thick, and 

 provided internally and externally, at a short distance from its 

 margin, with a strong yellowish-white rib ; inner lip very thinly 

 spread on the base of the penultimate whorl ; iivibilicus minute, 

 contracted by a basal ridge. 



Inhabits marshy places at the roots of grass. In this 

 country, the following are the only localities in which 

 it has as yet been found. Singleton near Swansea, 

 and the rejectamenta of the Avon River at Bristol 

 (J. G. J.), Tenby (Webster), Battersea Fields (Stephens), 

 Co. Clare (Humphreys), Milford, Yorkshire (Black- 

 house), Connemara, Co. Galway (Warren), B.C. Bun- 

 doran, Co. Donegal, and among moss and Jiinger- 

 viannia at Ballina, Co. Mayo (Miss Amy Warren). 



The shell of this species is smaller and narrower 

 than that of V. piisilla, its striation is stronger and 

 closer, and the mouth is narrower and provided with 

 fewer teeth. It is an inactive little creature, and when 

 crawling carries its shell perpendicularly. 



C. Shell dextral, cylindrical ; month destitute of teeth. 

 8. V. eden'tula,* Draparnaud. Pl. IX. 



Body darkish ash-colour above, paler on the sides as well as 

 underneath and behind ; tubercles very minute, blackish or 

 greyish ; mantle pale grey with a tinge of red ; tentacles blackish- 



Toothless. 



