X PREFACE. 



portance which have not hitherto been noticed,) to enable 

 the naturalist to define, more correctly than has yet been 

 done, the peculiarities of each species. 



A third object is to direct the attention of travellers 

 more particularly to this subject ; in order that, by their 

 exertions, our information upon this class of animals may 

 be rendered more complete. 



A new and important feature in the present Mono- 

 graph, is the introduction of a Table of the Number of 

 Vertebrae, carefully constructed from an examination of 

 the actual skeletons, by which will be seen at a glance 

 the principal osteological differences of species which have 

 hitherto been confounded with each other. A Table of 

 the Periods of Gestation is likewise added, which presents 

 some equally interesting results. 



Several of the descriptions have been verified by a 

 reference to the living animals, seven specimens of which 

 are at present (1847) in the Gardens of the Zoological 

 Society, Regent's Park. The several Museums in the 

 Metropolis have likewise been consulted with advantage. 



I am indebted to Judge FURNAM, of the United States, 

 for some original information respecting the American 

 Bison ; and also to the late Mr. COLE, who was forty years 

 park-keeper at Chillingham, for answers to several ques- 

 tions which I proposed to him on the subject of the 

 Chillingham Cattle. 



I beg to acknowledge my obligation to Mr. CATLJN for 

 kindly allowing me, not only to make extracts, but also 



