Plate 40 



1-32. Colobocentrotua Stimpsoni A. Ag. 

 1-32. Spines. 



1. Spine, from the buccal membrane close to the teeth. 



2. Spine, from the actinal system. 



3. 1 Spine, lower side, midway between the actinal system and the ambitus. 



4. i Spine, profile of same as 3. 



5. Spine, lower side, from the actinal side of tlie ambitus, from the left anterior 



ambulacrum. 

 6.1 Spine, upper side. 

 7. I Spine, lower side, from the actinal side near the ambitus, from the left anterior 



ambulacrum. 

 Spine, profile. 

 Spine, upper side. 

 Spine, lower side, at the ambitus, from the right posterior ambulacrum. These larger 



radioles vary in length from 12 to 15 mm. 

 Spine, profile. 

 Spine, upper side. 

 Spine, lower side, from the abactiual side, near the ambitus, from the left anterior 



ambulacrum. 

 Spine, profile. 

 Spine, upper side. 

 Spine, lower side, from the abactinal side near the ambitus, from the left posterior 



iuterambulacrum. 

 Spine, profile. 

 Spine, top view. 

 Spine, lower side, midway between the ambitus and the abactinal system, from the 



odd anterior ambulacrum. 

 Spine, profile. 



9. 



10. 



11- 

 12. 



13. 



14.. 



15. 



16. 



17-. 

 18.- 

 19. 



20.. 

 21.1 

 22 



Spine, top view. 



Spine, lower side, from the abactinal side towards the ambitus, from the left posterior 

 ambulacrum. 

 23. J Spine, profile. 



24. ■> Spine, upper side, from the upper extremity of the left anterior ambulacrum. 



25. ) Spine, lower side from the upper extremity of the left anterior ambulacrum. 



26. ) Spine, top view, from the upper extremity of the right posterior intei-ambulacrum. 



J. ) opine, 

 r. ) Spine, 



27. ) Spine, lower side from the upper extremity of the right posterior interambulaerum. 



28. Miliary spine, near the upper extremity of the right posterior interambulacrum, — 



hidden by the primary radioles. 



29. Miliary spine, lower side, from the anal system. 



30. Miliary spine, lower side, from the anal system. 



31. 1 Miliary spine, upper side, from the anal system. 



32. ) Miliary spine, profile, from the anal system. 



The figures are from the same specimen, measuring 88 mm. in diameter. 

 All the figures are about equally enlarged, except the shaded figures 1, 2, 5, 28, which 

 are considerably enlarged, as is shown by the adjoining outlines. 

 Bonin Ids., Dr. Wm. Stimpson Coll. 



