INTRODUCTION. 



TT may appear somewhat unphilosophical at first sight 

 J- to adopt insignificant topographical features of the 

 present era as the boundaries of a region of the earth to 

 be treated from a Palaeontological point of view, since many 

 of the specific types met with among the extinct faunae 

 represented in British rocks are well known to occur in 

 the corresponding beds of other parts of the world. From 

 the vastness of the subject, however, it is necessary to 

 assign definite narrow limits to the area under consider- 

 ation when attempting to record the actual state of 

 knowledge of any great group of extinct animals ; and 

 in this work, which deals exclusively with the Fossil 

 Vertebrata, it has therefore been deemed advisable to refer 

 only to forms occurring in Britain. The restriction does not 

 detract so seriously from the value of the result as might 

 be supposed ; for British Palaeontology is an epitome of 

 that of the whole world, and, although in some groups the 

 British fossils are comparatively fragmentary, there is no 

 other area of equal extent in which more variety is dis- 

 played. Almost every type of importance seems to have 

 some representative in our rocks. 



The earliest work of reference of a similar character is 

 the Synoptical Table of British Organic Remains, by 

 Samuel Woodward, published in 1830. At this date two 

 pages sufficed for the enumeration of the known British 

 Fossil Vertebrata ; and the progress of the next twenty 

 years is well illustrated by Professor John Morris' Catalogue 

 of British Fossils, which first appeared in 1843, an d com- 

 prised thirty pages devoted to the same group. In 1848-50 



