PREFACE. 



or very rarely a more extended meaning than its original 

 proposer applied to it. If this was not allowed, many new 

 names must be added to the list of genera, which is already 

 so overburdened with synonyma. In those cases where the 

 two sexes of the same species, or any particular individual 

 state or variety belonging to it, have been differently named, 

 the names belonging exclusively to the state or individual 

 described are placed after the reference to the specimens to 

 which they apply. To determine with accuracy the names 

 and synonyma of the species, the various specimens, skele- 

 tons and other remains of Hoofed animals in the Museums 

 of the Zoological Society, of the East India Company, of the 

 Naval Hospital at Haslar, and of the different local Societies, 

 especially those of Liverpool, Bristol, &c., and the various 

 continental Museums of Paris, Ley den, Berlin, Vienna, 

 and Frankfort, have been personally examined, and in 

 many cases the specimens contained in those Museums have 

 been sent to the Museum, so that they could be actually 

 compared with specimens in the Museum Collection. 



JOHN EDWARD GRAY. 



British Museum, 



1st December, 1852. 



