TAB. I. 



Fig. 



1 . Helix rysa, page 4. 



a. upper surface. 

 h. under surface. 

 c. front view. 



2. Helix arbustorum (?), p. 3. 



a. upper surface. 

 h. under surface. 

 c. front view. 



3. Helix hispida, /). 2. 



a. under surface. 

 h. upper surface. 

 c. front view. 



4. Helix pulcbella, yA 3. 



a. upper surface. 

 h. under surface. 

 c. front view. 



5. Succinea putris (?), p. 5. 



6. Succinea oblonga, p. 6. 



7. Limnsea pereoTa,^;. 7. 



a. front view. 

 h. back view. 



8. Limnsea truncatula (•'),/'. 8 



a. var. a. 

 h. var. /3. 



Fig. 

 9. Limnaea palustris {j:),p- 7. 

 a. front view, var. a. 

 h. id. var. /3. 



c. back view. 



d. front view of another specimen. 



10. Planorbis complanatus,^;. 9. 



a. under surface. 



b. upper surface. 



c. front view. 



1 1. Planorbis spirorbis, p. 9. 



a. upper surface. 

 h. under surface. 

 c. front view. 



12. Planorbis corneus. yj. 10. 



a. under surface. 

 h. upper surface. 

 c. front view. 



13. Conovulus pyramidalis, />. 11. 



a. front view. 



b. back view. 



14. Conovulus myosotis (r), j?>. 12. 



a. front view. 



b. back view. 



15. Conovulus myosotis (?), var. |3. 



The line-s indicate the size of the speciments. 



