No. 8.] J. W. DAWSON — PALEOZOIC LAND SNAILS. 



1. 2. 



453 



Fig. 1, Pupa vetusta, magnified 8 times lineally ; 2, same, showing 

 the aperture, X 8 ; 3, same, nuclear whorl, x 25 ; 4, same, mature egg 

 and embryo shell, X 25 ; 5, 6, Pupa Bigsbii, X 8 ; 7, Pupa Vermilionensis 

 X 8 ; 8, same, showing aperture, X 8, the small tooth on the colu- 

 mella somewhat exaggerated ; 9, same, section of aperture, showing 

 tooth X 16 ; 10, Zonites prisons, X 8 ; 11, same, crushed specimen, 

 showing aperture x 20. 



