Plate 29. 



1-17. ColobocentrotuB Stimpsoni A. Ag. 



1-17. Valves of pedieellarise. 



1. A valve 0.41 mm. of an Ophicephalous pedicellaria, exterior view, near the teeth. 



2. A valve 0.36 mm. 



3. A valve 0.48 mm. 



4. A valve 0.50 mm. 



Ophicephalous pedicellaria, interior view, near the teeth. 

 Ophicephalous pedicellaria, exterior view, nearer the actinal system 



than the ambitus, from the odd anterior ambulacmm. 

 Ophicephalous pedicellaria profile, interior view, nearer the actinal 



system than the ambitus, from the right anterior ambulacrum. 

 Ophicephalous pedicellaria, interior view. 



Ophicephalous pedicellaria, midway between the actinal system 

 and the ambitus, from the left anterior ambulacrum. 

 Tridentate pedicellaria, exterior view, not far from the actinal 

 system, from the left posterior ambulacrum. 

 Tridentate pedicellaria, interior view. 

 Tridentate pedicellaria, profile, exterior view. 

 Ophicephalous pedicellaria, showing the articulation near the am- 

 bitus, from the left anterior iuterambulacrum. 

 Ophicephalous pedicellaria, interior view, nearer the ambitus than 



the actinal system, from the right anterior interambulacrum. 

 Ophicephalous pedicellaria, interior view near the ambitus, from 

 the right anterior interambulacrum. 



Ophicephalous pedicellaria, exterior view midway between the 

 ambitus and the abactinal system, from the right anterior inter- 

 ambulacrum. 

 A valve 0.17 mm. Triphyllous pedicellaria, midway between the actinal system and 

 the ambitus, from the left anterior interambulacrum. 

 Triphyllous pedicellaria, from the same, interior view of a single 



valve. 

 Ophicephalous pedicellaria, interior view not far from the ocular 

 plate, from the left posterior ambulacrum. 

 Triphyllous pedicellaria, exterior view close to the ocular plate, 

 of the right posterior ambulacrum. 

 The enlargement of the pedicellaria of the actinal system is somewhat greater than that 

 of figs. 7-9 which are drawn on a smaller scale. 



All the figures are from a specimen 88 mm. in diameter including the spines. Collected 

 by Dr. Wm. Stimpson at the Benin Ids. 



12. A valve 0.47 mm. 



13. A valve 0.36 mm. 



14 



15. A valve 0.16 mm. 



16. A valve 0.34 mm. 



17. A valve 0.9 mm. 



