PLATE IV. 



Pentagonaster lunatus, Woodward, sp. (P. 25.) 

 From the Upper Chalk. 



FlQ. 



1 a. Actinal aspect of the type specimen ; natural size. (Coll. Norfolk and 



Norwich Mus.) 

 h. An actinal intermediate plate ; magnified. 

 c. An infero-marginal plate ; magnified. 



Pentagonaster megaloplax, Sladen. (P. 27.) 

 Frovi the Loiver Chalk. 



2 a. Actinal aspect of the example figured by Forbes, under the name of Cmdaster 



(Astrogonium) lunatus ; natural size. (Coll. Brit. Mus.) 

 /;. An infero-marginal plate; magnified 3 diameters. 

 c. Lateral view of the margin ; natural size, 



3 a. Actinal aspect of another example ; natural size. (Coll. Brit. Mus.) 



b. An actinal intermediate plate ; magnified 6 diameters. 



c. Adambulacral plates ; magnified 6 diameters. 



4 a. Actinal aspect of an example from the Upper Chalk of Bromley ; natural 



size. (Coll. Brit. Mus.) 

 h. Lateral view of the margin ; natural size. 

 r. Lateral surface of an infero-marginal plate; magnified. 



d. An infero-marginal plate ; magnified. 



e. An actinal intermediate plate ; magnified 6 diameters. 



