VI PREFACE. 



descent cannot be adequately understood without a fairly 

 infcimalte knowledge of recent Botany. 



The student of elementary geology is not as a rule required 

 to concern himself with vegetable palaeontology, beyond a 

 general acquaintance with such facts as are to be found in 

 geological text-books. The advanced student will necessarily 

 find in these pages much with which he is already familiar ; but 

 this is to some extent unavoidable in a book which is written 

 with the dual object of appealing to Botanists and Geologists. 

 While considering those who may wish to extend their botanical 

 or geological knowledge by an acquaintance with Palaeobotany, 

 my aim has been to keep in view the requirements of the 

 student who may be induced to approach the subject from 

 the standpoint of an original investigator. As a possible 

 assistance to those undertaking research in this promising 

 field of work, I have given more references than may seem 

 appropriate to an introductory treatise, and there are certain 

 questions dealt with in greater detail than an elementary 

 treatment of the subject requires. In several instances re- 

 ferences are given in the text or in footnotes to. specimens of 

 Coal-Mea.sure plants in the Williamson cabinet of microscopic 

 sections. Now that this invaluable collection of slides has 

 been acquired by the Trustees of the British Museum, the 

 student of Palaeobotany has the opportunity of investigating 

 for himself the histology of Palaeozoic plants. 



My plan has been to deal in some detail with certain 

 selected types, and to refer briefly to such others as should 

 be studied by anyone desirous of pursuing the subject more 

 thoroughly, rather than to cover a wide range or to attempt 

 to make the. list of types complete. Of late years there has been 

 a much wider interest evinced by Botanists in the study of 

 fossil plants, and this is in great measure due to the valuable 

 and able work of Graf zu Solms-Laubach. His Einleitung in die 

 Palaeophytologie must .long remain a constant book of reference 

 for those engaged in palaeobotanical work. While referring to 



