BEITISH FOSSILS. 



5 



Description of the Plate. 



Fig. 1. Diadema pseudodiadema, Lam., from Dr. Wright's specimen ; the apical plates 



are restored from one lent by Prof. Morris. 

 Fig. 2. Side view of do. 



Fig. 3. Part of the under surface, showing the deeply incised angles of the mouth and 

 the pores, a few only near to the mouth, in ranks of threes. 



Fig. 4. Portion of an ambulacral and of an interambulacral segment magnified ; the 

 pores in simple pairs, with a tubercle between each pair. 



Fig. 5. Part of an ambulacral segment near the mouth, shewing the pores in ranks of 

 threes, magnified. 



Fig. 6. Apical disk, with 5 minute ocular plates, and 5 large and nearly equal ovarian 

 plates ; the right anterior one a little the largest, and bearing the madre- 

 poric tubercle. 



Other British Species of Diadema. 

 In the second edition of Morris's Catalogue of British Fossils, Prof. Forbes had 

 materially increased the list of the British species of this genus. Of the new species there 

 recorded and referred to as described in this Decade, characters will be given, so far as the 

 materials permit, by our friend Mr. Woodward. In the arrangement of the species he 

 follows Desor, except that he regards his groups as subgeneric only. 



Notes on British Fossil Diademas. By S. P. Woodward, Esq. 

 * JuEASsic Species. 

 Section A. (Pseudodiadema, Desor.) Pores in single file. 



1 . D. pseudodiadema, Lam. Above described. 



2. D. Moorei, Wright, Ann. Nat. Hist., 1854., pi. 12. f. 3. 

 Localities. — Upper Lias, Ilminster ; also in Normandy. 



3. D. cequale, Ag., Ech. Suis., t. 17. f. 36-38. 



Locality. — "Coral Kag, Steeple Ashton ; M'Coy." Morris's Cat. 76. The original 

 specimen, in the Cambridge Museum, is a fragment of D. versipora (Diplopodia) ; 

 another, in the Brit. Museum, appears to be the real JD. aquale, but its locality is 

 not certain. 



4. B. depressum, Ag., Cat. 8. Wright, Ann. Nat. Hist, 1851, vol. viii. t. 12. f. 2. 

 Localities. — Bradford Clay, Cirencester. Great Oolite, Minchinhampton. In- 

 ferior Oolite, Crickley Hill and Dundry. 



4 a. D. armatum, Forbes, MS. Morris's Cat., 76. 

 Locality. — Inferior Oolite, Castle Carey, (not Gloucestershire), Somerset. 

 Represented in the Museum of Practical Geology by four small and imperfect 

 specimens, undistinguishable from small examples of D. depressum. 



5. B. mamillanum, Roemer, Ool., vol. i. p. 26. t. 2, f. 1. D. Davidsoni, Wright (1854). 

 Ann. Nat. Hist. vol. xiii. pi. 12. f. 2. 



Localities. — Coral Uag, Calue (Brit. Mus.) ; EedcliflF, near Weymouth (Geol 

 Survey.) 



The British specimens agree perfectly with specimens received from Dr. Ecemer, 

 labelled " XJ. Coral Bag, Hildesheim, Hanover." 



5 B 3 



