iv 



BRITISH FOSSILS. 



Of tlie ten species figured three are new, — Solaster Moreionis, 

 Cidaris Carteri, and Pygaster conoideus. Of the other genera, 

 Diadema, Echinopsis, and Echinus present us with well-known 

 types from the Oolitic rocks, which are continental as well as British. 

 Pyrina is a rare genus in England, and in this, and the two figured 

 species of Pygaster, we have excellent examples of that division of 

 the Gassidulidoe in which the ambulacra are of uniform character 

 throughout. Several genera of this type have been figured in the 

 Decades. The Pygaster semisidcatus is a critical species, and its 

 synonymy is now for the first time cleared up. Hemiaster Mur- 

 chisonice is another instance of the same kind, and belongs to a 

 large genus of closely allied species. The Brissus Scillce is a Crag 

 species still existing in the Mediterranean. None of these nine 

 genera have before appeared in the Decades. 



There are engraved plates sufiicient for another fasciculus, upon 

 which Professor Forbes left no memoranda, except the names of the 

 species. These Plates will be published at a future period. 



John W. Salter, 



Palceontologist. 



Geological Survey Office, Jermyn Street, London, 

 February 1856. 



