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Show 1871.] MR. ST. GEORGE MIVART ON HEMICENTETES. 59 ture specimens only *. Recently both our National Collection and the Museum of the Royal College of Surgeons have been enriched by skeletons of this species, and a very perfect and fully adult specimen in the possession of Mr. E. Gerrard has been very kindly lent m e for description and to supply the figures herewith given. These specimens have convinced me that the differences between the species now described and Centetes ecaudatus are of sufficient mportance to warrant the elevation of the former into a distinct genus. The external characters are so well known already that I shall confine myself to a description of the skeleton and dentition, pointing out the resemblances and differences between these parts in Hemicentetes and in Centetesf. Side, view of skull, twice the natural size. The skull is even more produced than is that of Centetes, but it is more tapering, more so, indeed, than in any insectivore, even Talpa. Thus, when looked at from above, it is much less cylindrical than in Centetes; and even when viewed laterally, it is at least as conical from behind forwards, in spite of the absence of the sagittal ridge which is so strongly marked in Centetes. The skull is broadest between the glenoidal surfaces, and then tapers forwards with considerable regularity. The orbits are not only incomplete behind, but there is not even any trace of a postfrontal process. Posteriorly the skull is rounded ; but anteriorly the nares slope gently backwards, with a very elongated opening. There is no zygomatic arch, but the maxillary process projects more backwards and less outwards than in Centetes; it ends in a sharp, rather upwardly inclined point. * He says, in ' Magasin de Zoologie,' 1839, p. 16, " il sera de toute evidence qu'elle n'a ete etablie que sur de jeunes sujets," and at p. 32, " O n ne connait que les caracteres du jeune age." t For a description of the skeleton and dentition of Centetes ecaudatus, see the 'Cambridge Journal of Anatomy,' vol. i. (1867) p. 298, and vol. ii. (1868) pp. 138, 139, and 148. |