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Show 282 MR. W. E. DE WINTON ON THE [Feb. 16, The figures of the skulls (pp. 280, 281) are taken from those of old wild-killed bulls now in the British Museum, the one from Abyssinia and the other from S. Africa. Mr. Selous tells m e that he has never seen a bull Giraffe with a third horn in South Africa, and Mr. Neumann says the same. Noticing the great difference in the weight of the skulls of the two sexes, I was curious to put them on the scales : taking the dried skulls of two wild-killed Abyssinian animals, I found that of the male weighed 19 lb. 8 oz., while that of the female only weighed 7 lb. 6 oz. The bones of the skull of the female are very smooth and thin; the whole of the upperside of the skull of the male is covered with a rough superficial osseous growth, which has its centre in tbe three horns, gradually enveloping the whole of the upper parts of the skull, forming lumps on the supraoccipital and supraorbital bones, and covering the face to the end of the nasals and the cheeks, so that all the true bones are completely hidden. Mr. Arthur H. Neumann-to whom I am much indebted for loan of specimens and help in working out the distribution, being well acquainted with the two forms, is perhaps the only hunter who has killed the Two-horned Giraffe both in South and East Africa, and also the Three-horned species, having formerly killed Giraffes in South Africa when they were much more plentiful than they now are and extended farther southward-tells me that on a journey from Mombasa as far as Usoga, on the route to Uganda, none were noticed but the southern or blotched kind, and that no Giraffes were seen west of the Naivasha Valley, the route taken from Naivasha to Kavirondo being more southerly than that at present followed by caravans. And writing to me on his recent successful hunting expedition to the northern shores of Lake Budolf, Mr. Neumann says :-" I only observed the southern variety in the neighbourhood of Athi or Sabaki Biver; I had a good view of one a little south of that river. The northern species I found from the Tana Biver northward as far as I went, namely, to the north end of Bassu (Lake Budolf) ; I mean, of course, the kind with the defined polygonal pattern. Whether or not there are any of this kind south of the Tana I do not know ; but I feel sure that in the direction I went it is the only sort to the north of that river. In some parts, particularly about the Guaso Nyiro, it is very plentiful, far more so than I have ever seen the southern type anywhere. From a little north of the Loroghi Mountains, I met with no more Giraffes until near the north end of the lake, where I noticed a few in one locality." N o w Mr. Neumann has thus proved that the two forms are not separated by any impassable mountain district or any great river, but that they approach one another on ground much less geographically or climatically distinct than parts within the ranges of either. This proves that there is no intermediate form, and therefore that to both must be given full specific rank. I must leave it to geologists to give a reason for this abrupt breaking off of the species ; it is the more interesting as it marks the southern limit to the range of Grevy's Zebra (Equusgrevgl), while it does not prevent |