PLATE XV. 

 Metopaster ungates, Forbes, sp. (Page 47.) 



Fig. 



1 a. Actinal aspect ; natural size. (Coll. Wright.) 

 b. Lateral view of the margin ; natural size. 



Metopaster Bowerbankii, Forbes, sp. (Page 42.) 

 jProm the Upper Chalk. 



2 a. Actinal aspect ; natural size. (Coll. Geol. Survey.) 



b. Lateral view of the margin ; natural size. 



c. An infero-marginal plate (weathered) ; magnified. 



d. Mouth-plates ; magnified. 



Mitraster Hunteri, Forbes, sp. (Page 59.) 

 From the Upper Chalk. 



3 a. Abactinal aspect ; natural size. (Coll. Brit. Mus.) 

 b. A supero-marginal plate ; magnified 3 diameters. 



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



b. An infero-marginal j^late ; magnified 3 diameters. 



c. E.xtremity of the radial region ; magnified 3 diameters. 



d. Abactinal intermediate plates, seen from within ; magnified 6 diameters. 



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

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



