VISCERA OF AN OKAPI. 



193 



Occipito-styloideus (text-figs. 7, 8, 9, o.si.m.). 



This muscle is peculiar to Ungulates, and extends from the 

 styloid process of the occipital to the upper portion of the styloid 

 bone. 



In the Giraffe and Okapi it was far larger than in any of the 

 other Ruminants examined (Antelopes and Sheep), and offers in 

 these two genera a striking contrast to the same muscle in 

 Antelopes, particularly as regards the area of the styloid bone 

 covered by its insertion. 



In connection with the insertion of this muscle it should be 

 noted that the styloid bone of the Giraffe and Okapi differs 

 markedly from that of other Ruminants in the form of its upper 

 extremity (text-fig. 10). 



Text-figure 7. 



O.ST.FI 



The upper end of the stylohyal of Okapia johnstoni, inner surface, showing 

 the insertion of the occipito-styloideus muscle. 



o.st.m., occipito-styloideus muscle ; st.h.m., tendon of stylohyoid muscle; 

 st. ph. in., stylo-pharyngeal muscle. 



In Ruminants in general, the posterior margin of this bone, 

 close to its upper end, is produced to form a prominent angular 

 process, to the tip of which is attached the tendon of the stylo- 

 hyoid muscle. This process stands out more or less transversely 

 to the length of the bone and shows a tendency to a downward 



