Fia. 
. Abactinal aspect; natural size. (Coll. Brit. Mus.) 
PLATE XIII. 
PENTAGONASTER MEGALOPLAX, Sladen. (Page 27.) 
From the Upper Chalk. 
A supero-marginal plate; magnified 3 diameters. 
Meroraster Mantewul, Forbes, sp. (Page 38.) 
From the Upper Chalk. 
. Abactinal aspect ; natural size. (Coll. Brit. Mus.) 
A supero-marginal plate (much weathered) ; magnified 3 diameters. 
The madreporiform body and surrounding plates ; magnified. 
. Abactinal intermediate plates ; magnified 6 diameters. 
. Abactinal aspect of the example figured by Forbes; natural size. 
Brit. Mus.) 
. A supero-marginal plate; magnified 3 diameters. 
. Actinal aspect of another example figured by Forbes; natural size. 
Brit. Mus.) 
. An infero-marginal plate; magnified 3 diameters. 
(Coll. 
(Coll. 
