PEEFACE. ix 



Falconer of his expedition to Caslimeer and Little 

 Tibet, in 1837-38, with notes and aj)pendices. 



Of the second volume certain of the memoirs have 

 been already published, but many now appear for the 

 first time, and particularly the important memoir and 

 memoranda on the fossil species of Rhinoceros ; while 

 all have received valuable additions from the author's 

 Note-books and letters. 



It is necessary to state that many of the memoirs 

 and notes now published were Avritten long before the 

 author's death, and that possibly he may have seen rea- 

 son subsequently to modify or change certain of the 

 views expressed. Any one who knew Falconer's ex- 

 treme caution, and the frequency with which he revised 

 and re-studied all his views and observations before com- 

 mitting them to the press, will probably feel that he 

 would have deprecated the exposure which has now been 

 made of what in some instances may have been only 

 first impressions of the specimens which he described. 

 But unfortunately, the powerful and discriminating in- 

 tellect which would have erased the error of first im- 

 pressions and moulded scattered observations into a har- 

 monious whole was gone ; and the question to be decided 

 was, whether or not the observations carefully made, 

 and in many instances minutely and accurately recorded 

 by a shrewd, experienced, and conscientious searcher 

 after truth, were to be for ever lost ? As an executor of 

 my departed friend, I have not hesitated in adopting the 

 alternative which I believe will conduce most to the 

 perpetuation of his name in Palaontological Science; 

 while I am not the less assured that the publication of 

 these volumes will meet with the approval "of his former 

 friends who still labour in the same field of research. 



