1907.] 



HORNS OF THE GIRAFFE. 



101 



(text-fig. 24). The wide-spreading base of the cone-like ossicusp 

 subsequently encroaches, it is true, over a large portion of the 

 frontal bone. In the adult both the parietal and the frontal are 



Text-fig. 24. 



j otm 



oce 



Lateral view of tlie skull and lower jaw of a very young Giraffe, measuring- 

 30"8 centimetres from the occiput to the anterior border of the premaxilla : 

 preserved in the British Mu.seum. The drawing is five-twelfths of the natural 

 size. 



oco., occipital crest; gt.l., Giraffine conical tumescence of the parietal bone, above 

 which is developed the lateral ossicone (p.oss.) ; sfp., the fi'onto-parietal suture; 

 ot.l., position of the lateral tumescence of the Okapi, absent here ; gt.m., position 

 of the median frontal tumescence of the Giraffe, which in this young specimen 

 is still entirely undeveloped ; ot.m., position of the median tumescence of the 

 Okapi's skull (basinasal) ; pl.v., praelacrymal vacuity ; can., bifoliate canine 

 (deciduous dentition). 



(From Trans. Zool. Soc. vol. xvi. p. 293.) 



enlarged and tumescent, and both enter largely into the com- 

 position of the lateral horn of the adult Giraflie (text-figs. 25 & 33). 

 The whole form of the skull is rendered diflferent in the two 

 genera by this relationship of the ossicone to the frontal exclusively 

 in the one, to the parietal primarily but not exclusively in the 

 other (see text-figs. 26 & 27). 



In a skull of a very young Giraffe (text-fig. 24), pi'obably about 

 a year old, preserved in the British Musevnn, the lateral ossicone 

 is seen to rest almost entirely on the parietal. A transverse 

 section (text-fig. 28, p. 104) shows that the anterior margin of the 

 enlarging base of the bone constituting the ossicone has spread — 



