KUNGL. SV. VET. AKADEMIBNS HANDLINGAE. BAND 48. N:0 5. 147 



I have now tried to show that the development of the pattern of the Giraffes 

 as it has reached its present maximum in the reticulata-type is analogous with other 

 phenomena among the Ruminants, if it is only assumed that the original pattern was 

 spotted. 



Nothing is known, of course, about the colour or pattern of the ancestors of 

 the Giraffes, but it does not appear at all improbable that they might have had the 

 pigment more or less concentrated round certain centres on an otherwise somewhat 

 paler ground colour. It is not needed to assume that these ancestral types should 

 have had a sharply defined spotted pattern. It is quite sufficient if they from the 

 beginning had had such rosettes of accumulated pigment as for instance often are 

 seen in red domestic cattle in Sweden as well of native as of Ayreshire breeds. This 

 is mentioned only as an analogy, but also because such a pattern appears to the 

 present writer as a probable starting point in the development from a comparatively 

 more or less' uniform to a spotted coat. A concentration of the pigment at and 

 around these centres would probably result in a blotched pattern. 



It is, of course, also possible that the first blotched pattern was developed as 

 the result of broken up longitudinal stripes which may have been present in the 

 early ancestors of the Giraffes, and of which the stripes on the hind quarters and 

 legs of the Okapi may be the only remnants saved up to the present date. The 

 occurrence of longitudinal stripes in the first coat of the young Ungulata belonging 

 to several widely distant groups (f. i Tapirs, Pigs, Deer etc.) appears to indicate that 

 this was the primitive pattern of the ancestral Ungulata. 



The specimen of O. c. reticulata which I shot on the northern side of Guaso 

 Nyiri below Chanler Falls was a splendid old bull with worn teeth and probably at 

 the height of its development. As can be seen from the photos of the skull (PI. 

 XIII fig. I) the azygous frontal horn is strongly developed. It rises from a broad 

 conical base and continues in a thick cylindrical portion which is rounded and trun- 

 cate at the end hke the main pair of horns. The basal portion of the azygous horn 

 is studded with small exostoses in front and on both sides but those of the right 

 side are larger (PL XIII, fig. 2). In front of this horn on the posterior portion of 

 the nasals is a somewhat bigger boss, which lies entirely on the right side of the 

 mesial line (PL XIII fig. 2). This skull is, however, by far not so dextral in its 

 development as that of a bull of G. c. tippelsMrcM Matsohie from Kilimanjaro 

 described by the present author at another opportunity.' The right of the main 

 pair of horns is basally a little thicker than the left, and the thickened basal portion 

 extends forwards nearer to the orbit than on the left side (PL XIII fig. 2). The 

 roof of the right orbit is provided with a small boss but is otherwise hardly thicker 

 than that of the left. The posterior or occipital pair of horns are not so typically 

 developed as in old males of the Baringo Giraffe, but there is an osseous thickening 

 on either side, and that of the right is the stouter, and it extends about 5 mm. 

 further laterally than the left. It is thus evident that this race is » right-headed », 



1 ^Mammals* (p. 35-37) in SjOgben's Wiss. Ergeb. Kilimandjaro Meru Exped. 



