346 



EXPLANATION OF PLATES. 



PLATE 52. 



14. Lorica cimolea Rv. (=volvox Rve.). Conch. Icon., . 237 



15. Lorica volvox Rve. Ross del., . . . . 237 



16. Lorica volvox Rv. (1 sq. mill, of girdle). Pilsbry del., . 237 



17. 18. Lorica volvox Rv. (posterior valve). Pilsbry del., . 237 

 19. Lorica volvox Rv. (anterior valve). Pilsbry del., . . 237 

 20,21. Lorica volvox Rv. (intermediate valve). Pilsbry del., 237 

 22, 23. Enoplochiton niger Barnes (posterior valve). Emer- 



ton del., 



24, 25. Enoplochiton niger Barnes (intermediate valve). 

 Pilsbry del., ......... 



26. Enoplochiton niger Barnes. Ross del., . 



27. Enoplochiton niger (surface). Q. J. M. S., 



28. Enoplochiton niger (surface). Q. J. M. S., 



29. Enoplochiton niger (girdle of a young specimen). Emer- 



ton del., .... . 



PLATE 53. 



30. 



Liolophura iucana Old. ( L. gaimardi Blv.). U. S. Expl 

 Exped., 



31. Liolophura gaimardi Blv. (girdle spines). Pilsbry del., 



32. Liolophura gaimardi Blv. Ross del., . 

 33-35. Liolophura gaimardi Blv. Pilsbry del., 

 36-40. Liolophura georgiana Q. & G. Voy. Astrol., . 



41. Liolophura japonica Lisch. (Girdle spines). Pilsbry del. 



42. Liolophura japonica Lisch. Ross del., . 



43,44. Liolophura japonica Lisch. Jap. Meeres-Conch., 



45. Liolophura japonica var. tessellata Pils. Ross del., 



46. Liolophura japonica var. tessellata Pils. Pilsbry del., 



PLATE 54. 



252 



252 

 252 

 252 

 252 



252 



240 

 240 

 240 

 240 

 241 

 242 

 242 

 242 

 243 

 243 



21, 22. Nuttallina scabra Rv. Pilsbry del., . . . .280 

 23, 24. Nuttallina californica Nutt. Pilsbry del., . . 279 

 25-27. Nuttallina alternata Sowb. Conch. 111., . . .281 

 28-30. Nuttallina cinerea Poli. Emerton del., . . .283 



31. Nuttallina cinerea Poli (edge of girdle x 100). Pilsbry 



del., 283 



32. Nuttalliua cinerea Poli. Test. Utr. Sic., . . . .283 



33. Nuttallina cinerea Poli (girdle x 50 ca.) Pilsbry del., . 283 



34. 35. Plaxiphora ovata Hutt. Pilsbry del., . ' . . 332 

 36-39. Plaxiphora ovata Hutt. (profile, posterior, dorsal and 



ventral views of posterior valve). Pilsbry del., . . 332 

 40. Plaxiphora ovata Hutt. (sculpture of intermediate valves). 



Pilsbry del., 332 



41-45. O. caliginosus Cpr. (=Liolophura japonica Lisch.) 



Emerton del., . ... .244 



46. Onithochiton amicorum Bd. Voy. Curacoa, . . . 249 



