Explanation of the plates. 



AU the figures have beeu drawn by means of the Camera lucicla and 

 to the same scale of 28 diameters. 



Plate I. 



Fig. 1—4. Eunicites simplex, H. Pincers? 

 5. » sp. Support? 



i 6. » cristatus, H. Large dental plate of the right side. 



7, 8. " hebes, H. Left form of large dental plate. 



> 9. The same. Dental plate of the left side of jaw apparatus. 

 10. Eunicites contractus, H. Left dental plate. 



" 11, 12. » serrula, H. Unpaired dental plates. 



i 13. coronatus. H. Paragnath. 



» 14. • » var. a. Paragnath. 



> 15. » » var. b. Paragnath. 



> 16. » » var. c. Paragnath. 

 17—20. 1 pusillus, H. Paragnath. 



21. Oenonites aspersus, H. Jaw plate of the left side. 



> 22. The same. »Eight» iaw plate, upper surface. 



22 a. The same. Under surface of the same, showing the aperture 

 for the insertion of the muscle. 



» 23. ffinonites major, H. »Left» jaw plate; upper surface. 



» 24. The same. Under surface. 



Plate II. 



Fig. 25. (Enonites naviformis, H. Left jaw showing upper surface. 



» 26. The same. Under surface. 



» 27. The same. »Right» jaw; upper surface. 



» 28. The same. Left jaw; upper surface. 



» 29, 29 a. The same. Upper and under surfaces of the same specimen. 



» 30. The same. Jaw of the left half; upper surface. 



i 31, 32. CEnouites curvidens, H. Jaws of the right half of the jaw- 



apjjaratus ; showing the upper surfaces. 



» 33. (Enonites parvulus, H. »Eight» jaw; upper surface. 



> 34, 34 a. 2 radula. Upper and under surfaces. 



» 35. s radula, var cristula. Upper surface. 



'■> 36. » securis, H. Jaw plate of left side; upper surface. 



» 37. » » var. basalis. »Left» jaw-plate; upper surface. 



' 38 — 40. » ? spiniger, H. Eight and left forms, showing the 



upper surface. 



> 41, 41 a. The same. Upper and under surface of the same specimen. 

 » 42. Arabellites hamatus, H. Pincer of the left side. upper surface. 



