TAB. XIII. 



Fig. 



1. Limnaea subquadrata. No. 41, p. 92. 



a. Front view. 



• b. Back view. 



2 and 3. Limnaea pyramidalis. No. 31, p. 84. 



a, a. Front views. 



b, b. Back views. 



4. Limnaea sublata. No. 35, p. 88. 



a. Side view. 

 /;. Front view. 



5. Limnaea mixta. No. 36, p. 88. 



a. Front view. 



b. Back view. 



6. Limnaea tumida. No. 39,^.91 . 



a. Front view. 



b. Back view. 



7. Limnaea convexa. No. 42, p. 92. 



a. Front view. 



b. Back view. 



8. Limnaea fusiformis. No. 38, p. 90. 



a. Back view of specimen from Headon Hill. 



b. Front view, ditto. 



c. Back view of ditto. Var. deformis, intermediate size. 



d. Front view of ditto ditto adult shell. 



e. Back view of ditto ditto ditto 



/, g. Front views of shells from Sconce. Intermediate stage 

 of growth. 



9. Limnaea columellaris. No. 40, p. 91. 



a. Front view. 



b. Back view. 



1 0. Limnaea costellata. No. 43, p. 93. 

 a and b. Front views. 



