PLATE XXIX. 



Pycinasteb crassus, n. sp. (Page 96.) 



From the Upper Chalk. 

 Fig. 



1. Actiual aspect of a small specimen ; natural size. (Coll. Brit. Mus., E. 2576.) 



2. Abactiual aspect of surface of arm of type specimen; natural si".e. (Coll. Brit. Mus., 35498.) 

 a. Supero-marginal plate ; magnified 3 diameters. 



3. Supero-marginal plate ; uatui'al size. (Coll. Brit. Mus., E. 2631.) 

 a. Side view of same ossicle ; natural size. 



4. Isolated veutro-lateral plate ; magnified 2 diameters. (Coll. Brit. Mus., E. 2632.) 

 a. Isolated plate from abactiual surface of disc ; magnified 2 diameters. 



5. Madreporite ; natural size. (Coll. Brit. Mus., E. 2628.) 



Pycinastkr .senonbnsis, Valette, sp. (Page 95.) 

 From the Upper Ghalk. 



6. Outer view of abactiual ossicle of disc ; natural size. (Dr. Blackmore's Collection.) 

 a. Side view of same ossicle; natural size. 



Nymphastee. TvUgosus, 11. sp. (Page 94.) 

 From the Lower Ghalk. 



7. Actinal aspect ; natural size. (Coll. Brit. Mus., 57516.) 

 a. Infero-marginal plate ; magnified 6 diameters. 



Staubanderasteb abgus, 11. sp. (Page 99.) 

 From the Upper Ghalk. 



8. Actinal aspect ; natural size. (Dr. Blackmore's Collection.) 

 a. One of the veutro-lateral plates ; magnified 2 diameters. 



9. Inner view of three ossicles isolated from a specimen in the British Museum ; figured by Forbes ; 



magnified 2 diameters. E. 2566. [See also Plate XXV, fig. 6.] 

 a. Outer view of same ossicles ; magnified 2 diameters. 



Abthbasteb cbistatus, n. sp. (Page 93.) 

 From the Upper Chalk. 



10. Side view of segment of arm, restored; natural size. (Dr. Blackmore's Collection.) 

 a. Outer view of a radiale ; magnified 4 diameters. 



h. Side view of same ossicle ; magnified 4 diameters. 



Abthbasteb Dixoni, Forbes, sp. (Page 91.) 



From the Upper Ghalk. 



11. Ossicle from abactiual surface of disc; natural size. (Coll. Brit. Mus., E. 5024.) 

 a. The same ossicle ; magnified 3 diameters. 



Metopasteb cobnutus, Bladen, sp. (Page 117.) 

 From the Upper Ghalk. 



12. Ultimate supero-marginal plate of adult specimen; magnified 2 diameters. (Dr. Rowe's 



Collection.) 



Ophiotitanos MAGNUS, II. sp. (Page 10(3.) 

 From tlie Louier Chalk. 

 13. Abactinal aspect; magnified 2 diameters. (Coll. Sedgwick Mus., Cambridge.) 



