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Fig. 8. 
Fig. 9. 
PLATE XX*. 
Page 
Figs. 1-10. PorcELLANASTER C#RULEUS, Wyville Thomson, . » | alsa 
. Abactinal aspect ; magnified 3 diameters. 
. Actinal aspect ; magnified 3 diameters. 
. Profile view ; magnified 3 diameters. 
. A portion of the actinostome, showing the buccal membrane, and an 
adjacent radial area ; magnified 5 diameters. 
. An actinal interradial area; magnified 6 diameters. 
. A terminal plate, abactinal aspect; magnified about 7 diameters. 
. Actinal aspect of the same ; magnified about 7 diameters. 
A pair of ambulacral plates, seen in profile ; magnified 5 diameters. 
Ambulacral plates seen from above; magnified 5 diameters. 
Fig. 10. Lateral view of the same, showing the adambulacral plates; magnified 5 
diameters. [The character of the latter is somewhat exaggerated. | 
[These figures appear to have been drawn from a dried or shrunken example. 
The plate was prepared under the direction of Sir Wyville Thomson, and I 
was unfortunately not aware of its existence until the greater part of the text and 
nearly all the plates had been printed off. | 
