PLATE 35. 
1-3. Colobocentrotus Mertensii Brandt. 
1, Seen from the actinal side. 
2. Seen from the abactinal side. 
3. The same specimen, seen in profile, facing the odd anterior ambulacrum. 
All figures are natural size. 
The odd anterior ambulacrum occupies the center of the upper part of figs. 1, 2. 
Bonin Ids., Captains Ringgold and Rodgers, N. P. Ex. Ex., Dr. Wm. Stimpson Coll. 
