PLATE 36. 



Page 

 Figs. 1 - 13. Spirifera oranulifera 22:{ 



1. Dorsal view of a small individual. 



2. Cardinal view of the same, showing great'height of area. 



3. Profile of same. 



4. Ventral view of another specimen, showing an angnlar mesial sinus. 



5. Ventral view of a well preserved and jwrfoct siwcimcn of the ordinary size. 



6. Dorsal view of the same. 



7. Profile of same, for comparison with flg. 3. 



8. Front view of same. 



9. Cardinal view of the same. 



10. Dorsal view of a larger and less gibbons specimen, showing more of the ventral area. 



11. View of the interior of a dorsal valve, showing the muscular impressions, area and dental 



aockets. 



12. View of the interior of a ventral valve, showing the muscular impression, cardinal area, 



and the callosity within the apex of the foramen. 

 18. Enlargement of a part of two plications, showing the granuloee structure of the surface. 



