24. Spine, side view, from the abactinal side, near the ambitus, from the right posterior 
interambulacrum. 
25. Spine, | profile, from the abactinal side, near the ambitus, from the right posterior 
interambulacrum. 
26. Spine, ) lower side, midway between the ambitus and the abactinal side, from the 
right posterior interambulacrum. 
27. Spine, | profile, midway between the ambitus and the abactinal side, from the right 
posterior interambulacrum. 
28. Spine, | top view, midway between the ambitus and the abactinal side, from the right 
posterior interambulacrum. 
29. Spine, ) lower surface, from the genital plates. 
30. Spine, > profile, from the genital plates. 
31, Spine, } top view, from the genital plates. 
32. Spine, side view, from the madreporic plate. 
33, Spine, from the abactinal side of the right posterior interambulacrum. These spines 
are hidden under the big primary radioles (see Pl. 11, fig. 7). 
The enlargement of the figures is about the same. The shaded figs. 7, 2, and 33 are 
drawn on a larger scale. ; 
Hawaiian Ids., A. Garrett Coll. 
