ACTION. 435 



of the shell : outer lip gently curved, not folding inwards : 

 inner lip forming a thin glaze on that part of the body-whorl 

 which lies within the mouth, and broadly reflected over the 

 lower part : pUlkrvery short and flexuous : fold or plait tooth- 

 like and strong, winding obliquely along the pillar : operculum 

 horny, long and wing-like ; the inner part has the aspect of a 

 Gristeitaria, with a nearly terminal spire ; the whole surface of 

 the operculum is marked by puckered lines of growth, and 

 the outer part is slightly and irregularly scored by curved and 

 other scratch-like striae. L. 0-75. B. 0-4. 



Yar. 1. subulata. Smaller and narrower, with an elongated 

 spire. A. subulatus, S. Wood, Crag. Moll. pt. 1. p. 170, t. xix. 

 f. 7 a, h. 



Yar. 2. tenella. Body milk-white : foot lanceolate and slender. 

 Shell smaller, thinner, semitransparent, more glossy, and of 

 a paler hue, sometimes without bands ; the young have the 

 middle of each whorl smooth. A. tenellus, Loven, Ind. Moll. 

 Scand. p. 11. 



Yar. 3. bullaformis. Smaller and regularly oval, with a 

 much shorter spire. 



Habitat : Sandy bays, at low-water mark of spring- 

 tides, to about 20 f. ; not uncommon, and widely dis- 

 tributed. Capt. Beechey dredged a dead specimen in 

 145 f. off the Mull of Galloway. Var. 1. Fishguard 

 and the Hebrides ; rare. Var. 2. Muddy sand in 80- 

 90 f., Shetland. Yar. 3. Loch Fyne, in mud, 40-50 f. 

 (A. M'Nab). This species occurs in a fossil state at 

 Belfast (Grainger) ; boulder-clay in Caithness (Peach) ; 

 Red and Coralline Crag at Sutton (Wood); post-glacial 

 beds in Norway, 50-100 feet, some specimens retaining 

 their coloured bands (Sars) ; lower Crag of Antwerp 

 (Nyst); Italian tertiaries (Scacchi and others); Germany, 

 Greece, and Vienna Basin (Homes). The 1st variety 

 is described by Wood from the Red Crag at Sutton. 

 A. tornatilis ranges from the Loffoden Isles (Sars), and 

 Iceland (Steenstrup) , to the iEgean (Forbes); depths 

 recorded 10-100 f. The variety tenella inhabits ^andy 



U 2 



