VI PREFACE TO THE SECOND EDITION. 



personal opinion, and it is therefore quite likely that some 

 of the forms which have not been alluded to may be thought 

 to be as important and as deserving of notice as those which 

 are actually selected for mention. So far as this point is 

 concerned, the Author can only say that he has acted to 

 the best of his ability, and that he by no means supposes 

 the selection actually made to be ideally perfect. 



It is hoped that most of the more important additions to 

 our knowledge of the great and rapidly-growing science of 

 Palaeontology will be found to be incorporated, in however 

 condensed a form, in the present edition. In this connec- 

 tion, however, the Author would wish to mention that the 

 greater part of this edition was written in the early part of 

 the year 1878, and that the whole of it was in the hands of 

 the printers before the commencement of the present year. 

 Owing to this fact, though considerable and unexpected 

 delay has occurred in the actual publication of the work, 

 it has arisen that the Author has been unable to avail him- 

 self fully, or at all, of some important palaeontological works 

 and memoirs which were published towards the close of 

 1878, and in the early part of the present year. Among 

 these may be more especially mentioned the Second Part of 

 the ' Handbuch der Palseontologie,' by Professors Zittel and 

 Schimper ; the memoirs of Munier-Chalmas and Toula upon 

 the Dactyloporidae ; the valuable memoirs by Mr Henry B. 

 Brady upon the Eeticularian Ehizopoda of the Challenger 

 and Arctic Expeditions ; the concluding portions of the 

 ' Beitrage zur Systematik der fossilen Spongien,' by Pro- 

 fessor Zittel ; the treatise of Professor Mobius upon the 

 structure of Eozoon Canadense ; the important Monograph 

 by Angelin upon the Cystideans ; the researches of Mr P. 

 Herbert Carpenter upon the Oral and Apical Systems of 

 the Echinoderms ; the Croonian Lecture by Mr Moseley 

 upon the Structure of the Stylasteridse ; and the valuable 

 papers upon the Dwarf Crocodiles of the Jurassic, by Pro- 



