104 NON-MAUINE FOSSIL MOLLUSCA. 



PLATE 12. LARAMIE. 



Ostrea glabra Meek & Hayden. (Page 15.) 



FlQ. 1. Interior view of an under valve of the variety 0. loyoiningetiaia Meek; from 

 Point of Rocks, Southern Wyoming. Natural size. • 



Ostrka subtrigonalis Evans & Shuniard. (Page 15.) 



Fig. 2. Exterior view of a lower valve. 



Fig. 3. Interior view of another example of the lower valve. 

 Fig. 4. Exterior view of an upper valve. 

 Fig. 5. Interior view of the same. 

 (All natural size.) 



Anomia microne.ua Meek. (Page 16.) 



Fig. 6. Exterior view of an upper valve, showing radiating lines of ordinary char- 

 acter. 



Fig. 7. Similar view of another example, the lines upon which arc very line, and less 

 conspicuous thau they appear upon the figure.. 



Fig. 8. Similar view of another example, having radiating lines much coarser than 

 usual. 



Fig. 9. Interior view of a large, nearly flat, upper valve, showing the tour muscular 

 scars, and the process beneath the beak. 



Fig. 10. Similar view of another example, showing the process more plainly ; but the 

 scars are obliterated. 



Fig. 11. Interior view, showing the under valve, with its byssal plug. 

 (All natural size.) 



Anomia gryphorhynchus M. (Page 16.) 



Fig. 12. Exterior view of a lower valve. 

 Fig. KJ. Similar view of two other valves. 

 Fig. 14. Lateral view of Fig. 12. 



Fig. 15. Interior view of an upper valve, showing the muscular markings and the 

 small process beneath the beak. 

 (All natural size.) 



