PLATE 112. 
Page 
Fig. 1 - 10, Platyostoma ventricosa. 
1 & 2. Young shells of this species. 
3. A young specimen, showing a broadly undulating surface. 
4 a. View of the aperture of the same. 
4 b. An older specimen of the ordinary form. 
5 a, b. View of the spire, and of the aperture of a specimen of medium size. 
5 c. Profile of a specimen which is somewhat depressed vertically. 
6. A young specimen with a more elevated spire. This is of the type of P. arenosa of Comrad 
( See Plate lvii). 
7 & 8. View of the spires of two specimens of ordinary form. 
9. A specimen which has been vertically compressed. 
10 a, b. View of a specimen which is a little compressed obliquely. 
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