vi INTRODUCTION. 



Professor H. G. Bronn's great work, the Index PalcEonto- 

 logiais, provided still more numerous references, incor- 

 porating the notices of British forms with those of similar 

 fossils occurring in other parts of the world ; and in 1854 a 

 second edition of Professor Morris' Catalogue was published, 

 still further extending the list, and including all genera 

 and species at that time known. Except in the Palaeozoic 

 groups, which are treated by Mr. R. Etheridge in his Fossils 

 of the British Islands, Part i (1888), the considerable 

 advances in British Vertebrate Palaeontology during the 

 last thirty-five years have not hitherto been systemati- 

 cally catalogued. The scattered form, however, in which 

 the numerous works and memoirs have appeared, renders 

 such a record almost essential for further progress ; and 

 the object of the present volume is to supply this deficiency 

 in the literature of the subject. 



Vertebrate fossils have been found in British strata of 

 as early a date as any known in other parts of the world ; 

 unless, indeed, the ichthyolites from Ohio described by 

 Professor E. W. Claypole are referable to a slightly lower 

 horizon than the English Ludlow, as already maintained. 

 The ventral shield of a Pteraspidian fish {Scaphaspi* 

 ludensis), now in the Museum of Practical Geology, was 

 long ago discovered in the Lower Ludlow of Leintwardine, 

 by the late Mr. John Edward Lee, F.G.S. The Upper 

 Ludlow Bone-bed has furnished undoubted fish remains 

 {e.g., Onchus and Cyathaspis), although some of the fossils 

 in Sir R. I. Murchison's collection, originally described 

 as such, may have been truly referable to invertebrate 

 animals, as remarked by M'Coy. All the Silurian Verte- 

 brata described and figured in the ' Silurian System ' 

 unfortunately seem to have been lost.* 



The Downton Sandstone, in the neighbourhood of 

 Ludlow, has also yielded shields of Pteraspidian fishes,, 

 due chiefly to the exertions of the late Messrs. R. W_ 



* R. I. Murchison, Qua) t. Joitrn. Geo/. Sec, vol. ix, 1853, p. 16. 



