VI PREFACE 



As in the first volume I have endeavoured in the index to 

 refer the reader to the page on which technical terms are 

 defined and most of the abbreviations are explained in the 

 same place. 



To Mr. J. J. Lister, F.R.S., I am again under very great 

 obligations. He has looked through all the proof sheets 

 and has given me the full benefit of his wide knowledge and 

 great critical powers. I am also indebted to his pencil for 

 the excellent illustrations on p. 341 and p. 532. 



My thanks are also due to Professor Newton, Professor 

 Ray Lankester, Mr. Boulenger, Professor MacBride, Pro- 

 fessor Graham Kerr, Dr. Chalmers Mitchell, Dr. Andrews, 

 Mr. Walter Heape, Mr. Assheton, Dr. Gaskell, Dr. Marett 

 Tims and others for the assistance they have given me in 

 different parts of the work. 



My principal sources of information are acknowledged in 

 the footnotes, but I must not omit to mention here works 

 from which I have obtained special help ; these are Gadow's 

 A^nphibia and Reptiles and Evans' Aves in the Cambridge 

 Natural History, Flower and Lydekker's work on Mammalia 

 Living and Extinct, Smith Woodward's Outlines of Vertebrate 

 Palaeontology and Zittel's Grundriss der Palaeontologie, and 

 Gunther's I^itroduction to the Study of Fishes. The excel- 

 lent volume on fishes in the Cambridge Natural History and 

 Weber's great work on the Saugethiere appeared too late to 

 be utilised. 



Of the illustrations about fifty are new ; of the remainder 

 a considerable number are from Claus' Lehrbuch, but some, 

 of which I have been permitted to make use by the 

 courtesy of the author and publisher, are from Smith 

 Woodward's Vertebrate Palaeontology, Reynold's Vertebrate 

 Skeleton, Flower and Lydekker's Mammalia Living and 

 Extinct, Flower's Osteology of Mammalia, Huxley's Anatomy 

 of Vertebrate Animals, Shipley and MacBride's Zoology, 

 Zittel's Grundzuge der Palaeontologie, Korschelt and Heider's 

 Text Book of Embryology, Gegenbaur's V ergleichende 

 Anatomic der Wirbelthiere, Wiedersheim's Grundriss der 

 Anatomic der Wirbelthiere, Perrier's Traitc dc Zoologie, 



