PREFACE. 



The preparation of the 'Monograph of the Okapi,' on which Sir Ray Lankester 

 was engaged when he retired from the Directorship of the Natural History Department* 

 of the British Museum, has taken longer than was expected. As the lithographic plates 

 were printed off and the blocks originally intended for use as text-figures were 

 made two years ago, it was suggested that all the illustrations should be published 

 forthwith in the form of an Atlas of Plates without waiting for the text. Sir Ray 

 Lankester concurred cordially in this proposal, and the plates have accordingly been 

 arranged for publication by Dr. W. G. Ridewood, who has also written appropriate 

 legends. 



The material on which the Atlas is based consists in the first place of the series of 

 skins, skulls and other bones in the British Museum, and in the second place of 

 specimens which have been lent for the purpose of illustration and of photographs 

 given by museums or private owners. Special thanks are due to Sir H. H. Johnston, 

 G.C.M.G., the late Mr. Boyd Alexander and Major Powell-Cotton for the presentation 

 of specimens of the Okapi, and to the Hon. Walter Rothschild, Mr. Rowland Ward, 

 Mr. W. Eagle Clarke, and the directors of numerous foreign museums for the loan of 

 specimens or for the gift of photographs. The figui'es which it has thus been possible 

 to put together in Plates 1 and 29—46 illustrate the variability of the skin-markings, 

 while those of skulls shown in Plates 2 — 18 constitute an important contribution to the 

 discussion of the problem as to the existence of two races of Okapi, with " broad " and 

 " narrow " skulls respectively. 



At is doubtful whether the Atlas will be followed by a volume of text at a later 

 date. The necessity for publishing the text is less great than it was when the 

 work was originally projected, in consequence of the appearance of Fraipont's large 

 monograph in ] 907, of the paper by M. de Rothschild and H. Neuville in the present 

 year, and of other publications on the same subject. It is hoped, however, that the 

 illustrations will speak for themselves, and that they will be of service as a contribution 

 to our knowledge of the rare animal which forms the subject of this Monograph. 



SIDNEY F. HARMER, 



Keeper of Zoology. 



British Museum (Natural History), 

 May, 1910. 



in 



