PLATE XVIII. 
PENTACRINUS WYVILLE-THOMSONI, Jeffreys. 
1. The head, with the upper part of the stem, 
2. The calyx and arm-bases, 
3. A young specimen, 
gs. 4, 5. Upper and lower views of the radial pentagon, 
os. 6, 7. An isolated basal from below and above, 
8, 9. Proximal and distal faces of the third (axillary) radial, 
. 10,11. Proximal and distal faces of the second radial, 
Diam. 
4 
) 
2 
3 
3 
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30 
293 
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