PLATE XVI. 

 Metopasteb Boweebankii, Forbes, sp. (Page 42.) 



From the Upper {?) Chalk. 



Fig. 



1 a. Abactinal aspect of the example figured by Forbes , natural size. (Coll. 

 Brit. Mus.) 



h. Lateral view of the margin ; natural size. 



c. Tbe last three supero-marginal plates ; magnified 2 diameters. 



cl. Abactinal intermediate plates ; magnified 6 diameters. 



Metopastee Parkinsoni, Fortes, sp. (Page 31.) 



From the Upper Chall\ 



2 ft. A pair of ultimate supero-marginal plates and the odd terminal or " ocular" 

 plate ; magnified 2 diameters. (Coll. Brit. Mus.) 

 h. Lateral or marginal view of the same ; magnified 2 diameters. 



MiTRASTER EUGATUS, Forbss, sp. (Page 63.) 



From the Upper Challc. 



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



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

 4. Supero-marginal plates of another example ; magnified 2 diameters. (Coll. 



Brit. Mus.) 

 5 a. Abactinal aspect of the example figured by Forbes ; natural size. (Coll. 

 Brit. Mus.) 

 h. Lateral view of the margin ; natural size, 

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



(1. Profile or sectional view of the margin, showing a supero-marginal and an 

 infero -marginal plate ; magnified 3 diameters. 



