PLATE IP. 



Dorocidaris papillata, f. 1-13. 



1. Single jaw (pyramid) seen from outside of lantern. 



1. Same in profile, showing striation of lateral face. 



3. Base of pyramid (inside of lateral face) in profile. 



4. " " " from interior of jaw. 



5. Pyramid seen from above. 



6. Part of upper end of pyramid side plate (exterior.) 



7. « " " " " " " " (interior.) 



Arbacia pustulosa, f. lH-i 



Echinothrix turcarum, /. . 



34. Pyramid, interior of lateral face, in pi'ofile. 



35. " seen from outside. 



36. " " in profile. 



37. " " from above. 



38. Upper part of pyramid. 



39. Interior of upper part of pyramid. 



40. Brace seen in profile. 



41. Brace seen from below. 



42. " " " above. 

 43-45. Compass. 



46. Single tooth in profile. 



47. " " from inside. 



48. " " " outside. 



Hipponoe variegata, / 49-61. 



49. Single pyramid from without. 



50. " " in profile. 



51. " " " " interior of lateral fece. 



52. Part of lateral face. 



53. Upper part of pyramid (exterior.) 



54. Pyramid from above. 



55. Brace fi'om below. 



(^AU Jigs, of jaips (^pyramids) natural size, others slightly magnijieil.) 



