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PLATE 86. 
1-5. Pilematechinus Rathbuni A. Ag.; Station 3374. 
. Part of ambitus and adjoining abactinal coronal plates to show the resorption of 
the primary tubercles in a specimen 95 mm. in length. 
Part of fifth and sixth plates from the mouth, showing primary tubercles in different 
stages of resorption, from the right anterior ambulacrum. 
Seventh plate from the mouth, showing partly and wholly resorbed tubercles in the 
region crowded with primary tubercles of the odd interambulacrum of a specimen 
85 mm. in length. 
One of the plates of the odd interambulacrum, seen from the interior, showing the 
splitting up of a primary plate of a specimen 85 mm. in length. 
Anal system of a specimen 95 mm. in diameter. 
