PLATE III. 



Fig. 



1 . An internal cast of Pteraspis Crouchii, showing the form of the concave part of the 



anterior rostrum. Herefordshire. Rev. J. Crouch. 



2. A cast (laterally compressed), with the posterior spine attached. It shows well 



the radiating ridges. Herefordshire. 



3. A similar specimen, not compressed. Herefordshire. 



4. Cast of Pteraspis shield, probably Pt. Crouchii, in yellow sandstone. Shropshire. 



Mr. Wyatt-Edgell. 



5. Rostrum of Pt. Crouchii, showing anterior dorsal surface and cast of posterior 



ventral surface. Rev. J. Crouch. 



6. Rostrum of Pt. Crouchii, showing anterior under surface. From Mr. Lightbody's 



cabinet. 



7. Portion of disc. Herefordshire. 



8. The only specimen showing the tapering rostrum attached to the cordiform disc. 



Acton Beachamp, Herefordshire. Mr. Humphrey Salwey. 



9. Portion of disc, with surface-striations preserved. Herefordshire. Mr. Wyatt- 



Edgell. 



10. An unusually well-marked cast of the disc. Herefordshire. M. P. G. 



11. Rostrum. Herefordshire. Dr. Grindrod. 



12. Part of rostrum in cast. 



13. View from below of a specimen of the rostrum, showing its excavated portion. 



Herefordshire. Mr. Lightbody. 

 13 «. Lateral outline of the same specimen, showing upward flexure. 

 All the figures are of Pt. Crouchii. 



