118 LIMN^ID^. 



inner Up rather thick : fold somewhat prominent and sharp. 

 L. 0-6. B. 0-2. 



Yar. elongata. Spire more produced, so as to alter the 

 relative proportions of length and breadth. 



Habitat : Ditches and shallow pools, but sparingly- 

 distributed in this country. It appears, however, to have 

 been found in the following counties and places, — viz. 

 Northumberland, Durham, York, Salop, Norfolk, Suffolk, 

 Essex, Oxon, Wilts, Dorset, Cornwall, Guernsey, Jersey, 

 Cork and Belfast. Although local, it is plentiful where 

 it occurs. It ranges from Scandinavia to France as far 

 south as the lower Pyrenees, 



It is an exceedingly sluggish and timid mollusk, but 

 ventures occasionally on a very short floating excursion. 

 It often retires considerably within its shell, when it 

 forms the inside lip or rib. The repetition at intervals of 

 this lip, which is seen through the semitransparent shell, 

 gives the latter a varicose appearance. The shell is also 

 liable to lose its first or apical whorls, and consequently 

 to become decollated. 



This species is the Bulimus leucostoma of Poiret, Helix 

 octanfracta of Montagu, and lAmneus elongatus of Dra- 

 parnaud. 



Genus IV. AN'CYLUS*, Geoffroy. 

 PL IV. f. 11, 12, 13, 14. 



Body oval, conic, slightly twisted behind ; head very large : 



tentacles short, nearly cylindrical but thicker at their base : 



foot oval, or oblong, obtusely rounded in front and behind, 



closely attached to the upper part of the body : respiratory 



pouch or sac forming a short tube. 



Shell hood-shaped, with an incomplete or rudimentary spire, 

 which is in some species dextral and in others sinistral. 



* Hooked. 



