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it is perhaps the most remarkable snail found in the district. 

 Ancylus is the last freshwater genus ; and the two species 

 A. fluviatilis, Miill. and A. lacustris, L., are found in streams 

 and ponds adhering, like minute limpets to plants and 

 stones. 



Among the land mollusca there are many more gaps. Out 

 of 90 species only 79 are so far recorded. Of the 15 slugs 

 three are absent ; the first of these, Geomalacus niaculosus, 

 Allman, is exclusively Irish; the next, Avion Jiavus, Miill., is 

 a doubtful, almost a mythical species, included in the list on 

 the authority of a specimen which there is very little doubt 

 was merely a variety of the common Arion ater, L. Liinax 

 tenellus, Miill., north of England only, Shetland and Northum- 

 berland. Both species of Testacella are included among the 

 remaining 12. Testacella haliotidea, Drap., the commoner of 

 the two, is probably much more widely distributed than is 

 generally imagined, for though conspicuous in appearance it is 

 of a retiring nature. The greater part of its life is spent 

 underground ; but after heavy rains it may sometimes be seen 

 in gardens, crawling over beds and paths, and its light yellow 

 colour, even without the small shell on its tail, renders it 

 unmistakable. Its diet consists almost exclusively of worms ; 

 and I have known it found on one or two occasions by people 

 who, going out on wet nights to collect worms for a fishing 

 expedition, have found Testacella hunting also. Its manner of 

 eating them strikes us as being rather cruel, a slug three inches 

 long will attack a worm perhaps considerably longer, and 

 having swallowed as much as it conveniently can, will digest 

 that quietly, while the remainder writhes and wriggles about 

 outside till it is eventually drawn in. Succinea is the next 

 genus after the slugs, and we have four out of five species, the 

 one absent 6". oblonga, Drap., being exceedingly rare. These 

 shells vary so much that it would be possible to arrange a 

 series showing almost perfect gradation from 6". pfeifferi, 

 Rossm., to 5. putris, L., and no two conchologists would draw 

 the dividing lines in the same places. Vitrina, one species. 

 V. pellucida, Miill., common. Hyalina = Zonites, ten species, 

 all represented. Helix, twenty-six species, four of which are 

 absent. Of these one H. lamellata, Jeff., is found only in the 

 north of England and Scotland ; the second, H. villosa, Drap., 



