IS 





ifp-,t;t 





Figure 12-3. Scanning electron micrographs of the inner 

 shell layer of Geukensia demissa showing fine-grained 

 structures reflective of extensive shell dissolution during the colder 

 months of the year (February sample). 



NOTE: Stereo pair was taken with a 6° angular displacement between expo- 

 sures. x3000. 



170 



