INTRODUCTION. 3 



available for the study of the fossil flora of East Yorkshire was 

 obtained by their means. It is to be regretted that very little 

 serious collecting has been undertaken during the last half-century ; 

 some of the famous localities which afforded so rich a harvest sixty 

 or seventy years ago are probably almost worked out, but there is 

 undoubtedly much valuable material to be found if local enthusiasm 

 were again aroused. William Bean and his nephew John Williamson 

 rendered excellent service in the early days of the geological 

 exploration of the Yorkshire coast : the characteristic handwriting 

 of the former is met with in most of our Museums on the labels 

 of Yorkshire fossil plants ; the latter began life as a gardener at 

 Scarborough, 1 and afterwards became Curator of the Scarborough 

 Museum, which owes many of its treasures to his skill as a scientific 

 collector. John Williamson in later life was assisted in his natural- 

 history work by his son William Crawford Williamson, whose 

 brilliant palaeobotanical researches date from his boyish days, when 

 his father's zeal led him to take a share in interpreting the 

 records of Jurassic life. The elder Williamson was acquaintril 

 with William Smith, whose name will always be prominently 

 associated with Jurassic geology, 2 and with Smith's nephew, John 

 Phillips, whose work on the Yorkshire Coast is one of the English 

 classics. Adolphe Brongniart 3 was at this period engaged on his 

 famous work on the history of fossil plants, and as the recognized 

 authority received various Yorkshire specimens for identification, 

 some of which he figured and described. 



The following list includes the East Yorkshire species described 

 by Brongniart in 1828 : 



Equisetum columnare = Equisetites columnaris, Brongn. 



Pachupteris lanceolata \ 



T> > = Pachypteris lanceolata, Brongn. 



Sphenopteris Williamsonis S. Willianuoni, Brongn. 

 S. erenulata = ? Coniopteris hymenophylloides (Brongn.). 4 

 S. denticulata = ? S. Williamsoni, Brongn. 

 S. hymenophyUoides = Coniopteris hymenophylloides. 

 Cyclopteris digitata Ginkgo digitata (Brongn.). 



1 Williamson, "W. C. (96), p. 3. 



2 Vide Phillips (44), p. 110, and Judd (98), p. 103. 



3 Brongniart (28 l and 28 J ). 



4 The parentheses enclosing an author's name indicate that the generic name 

 has been altered since the institution of the species [vide Seward (98), p. 111]. 



