1894.] NATURAL SCIENCKS OF PHILADELPHIA. 89 



Fig. 13. Dorsal view of valve viii. ' 



Fig. 14. Lateral view of valve viii. 

 Fig. 15, Ventral view of valve viii. 



Plate III. 



Figs. 10 to 20. Acanthochites asbestoidcs Carpenter. 



Fig. 16. Veutral view of valve vi. 



Fig. 1 7. Dorsal view (outline) of valve vi. 



Fig, 18. Lateral view of valve viii. 



Fig. 19. Ventral view of valve viii. 



Fig. 20. Dorsal view of valve viii. 



Figs. 21 to 26. Acanthochites Coxi Pilsbry. 



Fig. 21. Sculpture from middle of a side- area, x 22. 



Fig. 22. Posterior view of valve viii. 



Fig. 23. Lateral view of valve viii. 



Fig. 24. Dorsal view of valve viii. 



Fig. 25. Veutral view of valve viii. 



Fig. 26. Dorsal view of valve vii. 



Plate IV, 



Figs. 27 to 30. Acanthochites Mattheicsi Bednall and Pilsbry. 



Fig. 27. Dorsal view of valve vii. 



Fig. 28. Dorsal view of valve viii. 



Fig. 29. Lateral view of valve viii. 



Fig. 30. Dorsal view of entire animal, natural size. 



Figs. 31 to 33. Acanthochites speciosas H. Adams. 



Fig, 31, Dorsal view of valve viii. 



Fig, 32, Lateral view of valve viii. 



Fig. 33. Posterior view of valve viii. 



Fig. 34, Acanthochites Coxi Pilsbry : dorsal view of an alcoholic 



specimen, natural size. 

 Fig, 36, Acanthochites retrojectus Pilsbry: dorsal view of an 



alcoholic specimen, natural size. 

 Fig. 37. Acanthochites granostriatus Pilsbry: dorsal view of an 



alcoholic specimen, natural size. 



