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Show 1904.] SUBSPECIES OF GIRAFFA.CAMELOPARDALIS. 203 local forms of the Bonte-Quagga, which apparently grades imperceptibly into the typical race, has been accorded (although I think wrongly), in a late issue of the Society's ' Px-oceedings' *, specific x-ank. I should mention that I am much indebted to Mr. Rowland Ward, of 166 Piccadilly, and his staff in connection with tlxe subject of this paper, which indeed could scarcely have been written at all apart from their valuable assistance. Before proceeding to the descriptive part of m y subject, I may take the opportunity of recording a few general remarks with regard to tlxe local x-aces of Giraffa camelopardalis, the geographical range of which once extended from, or nearly from, the Cape to tlxe Egyptian Sudan and Abyssinia. Two features are noteworthy in regard to these local forms, some of which probably inter-grade. Firstly, we notice as we proceed fx-om south to north the gradual passage of a two-horned animal into one (so far as tlxe males are concerned) with three horns. But the development is by no means simply progressive, for we find in the eastern districts of the continent a tendency to the formation of a five-horned, and even of a six-horned, race. Secondly, proceeding in the same direction, a transition is observable from a blotched animal (that is to say, one with irregular dark chocolate-coloured blotches on a tawny ground) with dark legs spotted down to the hoofs, to one in which the max-kings take tlxe form of a white or huffish network on a chestnut or liver-coloured ground, while the lower portion of the legs becomes unspotted white; the culmination of this type being-presented by the Somali G. reticulata. Here, however, as in the case of tlxe horns, the progression is by no means regular, since we find in East Africa a strong tendency to the development of a stai'-like type of coloration. Indeed, it would seem that in this part of the continent Giraffes have, so to speak, got completely oft' the line, and run riot, both ixx the matter of colox-atioxx and horn-development. By no means the least noteworthy feature in regard to the change of tlxe type of coloration in Giraffes as we proceed from South to North-east Africa, is that it is precisely the reverse of that among tlxe Quaggasand Bonte-Quaggas. That is to say, that whereas among the various races of Giraffe the genex-al colour lightens and the legs pass from spotted to pure white as we go from south to north, among tlxe local forms of Equus burchelli the stripes on the legs, underparts, and hind-quarters, which are fully developed in the northern types, such as E. burchelli granti, have disappeared more or less completely in the southern forms, the supreme development in this respect being reached by the true Quagga (E. quagga). In the case of the Quagga-group, a satisfactory and sufficient explanation of the reason for the colour-change has, I think, been given by Mr. Pocock f. As regards the cause of the change in the reverse direction px-esented by the Giraffes, I have not hitherto * P. Z. S. 1901, vol. ii. p. 503, pi. xxix. f 'Nature,' vol. lxviii. p. 356 (1903). |