1907.] COLOUR-STRIPING OF THE FACE OF GIRAFFES. 125 



(text-fig. 41, p. 119). In one Somali specimen [G. reticidafus) the 

 haii's are entirely white over a large part of the region of the face 

 where the horizontal bands are developed. Yet these horizontal 

 bands show up very distinctly on account of the more erect setting 

 of the hairs (see text -figs. 47 &, 48). In some cases the hairs of 

 these ridges seem to have yielded more readily to destructive 

 processes connected with taxidermy than have the hairs of the 

 neighbouring tracts, and consequently the bands are marked out 

 by nearly bald furrows or pathways. 



Another point of interest is that one of the horizontal pre- 

 orbital hair- bands in the adult Giraffe directly leads up to the 

 pre-oi"bital hair-whorl, and that the position of this hair-whorl 

 appears to be farther in front of the eye in the Somali G. reticu- 

 latus than in other Gii"affes, whilst undoubtedly the hair is more 

 erect and strongly developed on those ridges and on the hair- 

 whorl in that species than in the other Giraffes which I have 

 been able to examine. 



It would be interesting to ascertain how far the varying 

 development of these colour-bands and paiuUel hair-ridges on the 

 face of the Giraffe is constant in the difterent local varieties of 

 Giraffe which have been distinguished. This is not a matter with 

 which I am at present able to deal. The purpose of the present 

 communication is to call the attention of zoologists to a banded 

 structure of the integument of the face in Giraffes which results 

 in the appearance of dark and light parallel bands of hair and in 

 the formation of strongly- marked parallel fringes or ridges of 

 erect hair separated by bands of recumbent hair. These struc- 

 tures are recorded in a foetal and in adult Giraffes, and appear to 

 have hitherto escaped attention. 



The production of optically effective colour-bands by the mere 

 crowding and direction of hairs along certain lines, without actual 

 difference in the pigmentation of the hairs of the lighter and 

 darker stripes, has possibly some significance in regard to the 

 origin and development of the more definite striping of the 

 mammalian pelage so frequently shown, when dark and light 

 stripes distinguished from one another are caused by the actual 

 presence of pigment in the hair of the dark stiipes, and its 

 absence in the hair of the lighter or white stripes. 



EXPLANATION OF PLATE V. 



Coloured drawing of the head and face, seen from above, of the foetus of a 

 Giraffe removed from its mother which died in the Society's menagerie in April 

 1906. 



The head of the foetus measured seven inches and one quarter from the anterior 

 angle of the base of the outer ear to the extreme border of the upper lips. 



The specimen had been preserved in alcohol for six months. 



Details concerning the parentage &c. of this foetus are given bj- Mr. Beddard in 

 Proc. Zool. Soc. 1906, p. 626. 



