Plate 37. 

 1-3. Colobocentrotua Stimpsoni A. Ag. 



1. Seen from the actinal side, measuring 88 mm. in diameter including the spines. 



2. The same seen from the abactinal side. 



3. Profile of the same facing the odd anterior ambulacrum. 

 All figures are natural size. 



Bonin Ids., Captains Ringgold and Eodgers, N. P. Ex. Ex., Dr. Wm. Stimpson Coll. 



