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Show 1895.] HEDGEHOG EROM SOMALILAND. 415 had the opportunity of examining, in London, some of the specimens described by Fitzinger, preserved in the Vienna Museum. After a careful consideration of all the materials which have come under m y observation, I have arrived at the conclusion that this Hedgehog from Somaliland belongs to a species new to science. I have found, in the British Museum, the skin of the body (spines only) of a Hedgehog from Taf, in Central Somaliland, which seems to be identical with it. The registered number of this specimen is 85.12.10.2. I propose to designate the new species E. sclateri. It belongs to that section of the genus in which the pterygoid fossa3 are well-developed, and in which the pterygoids do not contribute to the enlargement of the auditory chamber of the macerated skull. The following species, besides E. sclateri, fall under this division, viz., E. europceus, Linn., E. concolor, Martin, E. algirus, Duv. & Lereboullet, E. frontalis, Smith, E. auritus, Pallas, and those which are doubtfully distinct from the last, e.g., E. grayi, Bennett, E. megalotis, Blyth, and E. allulus, Stoliczka; and, finally, E. albiventris, Wagner, in which the hallux is absent, is also a member of this group. In the second section of the genus the pterygoid fossae almost disappear, the pterygoids being enlarged and bullate, the cavity contributing to the enlargement of the auditory chamber of the prepared skull. The Hedgehogs which present this type of cranial structure are E. micropus, Blyth, E. pictus, Stoliczka, E. cethiopicus, Ehrenberg, and E. macracanthus, Blanford. The Hedgehogs of the first section are referable to two subdivisions, depending on the nature of the post-glenoid process of the squamous. In one that process is soli4 and much smaller than the mastoid, whereas in the other it is as large as the mastoid process, and concave internally, but not bullate. The following species, viz., E. europceus, E. concolor, E. algirus, E. frontalis, E. sclateri, and E. albiventris, fall under the first of these subdivisions, and E. auritus and its allies already mentioned under the second. All Hedgehogs belonging to the first subdivision, and of which E. europceus may be regarded as the representative, have an area from the forehead to the nape devoid of spines. Their spines are perfectly smooth, that is they have no longitudinal ridges, and are circular in transverse section. They present, however, a finely striated appearance externally, due to the cells of their cuticular covering. In the Hedgehogs of tbe second subdivision there is no bare area on the mesial line of the head, and the spines are covered with longitudinal ridges bearing minute nodosities. In the second great section of the genus with dilated pterygoids the post-glenoid process of the squamous becomes greatly enlarged antero-posteriorly, and hollowed out into a large bullate cavity continuous with the auditory chamber of the macerated skull. The Hedgehogs belonging to this type of skull, and of which E. cethiopicus may be regarded as the highest expression, have a bare area |
