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Show 1887] MR. G. E. DOBSON ON THE GENUS MYOSOREX. 575 4. On the Genus Myosorex, with Description of a new Species from the Rio del Rey (Cameroons) District. By G. E. DOBSON, M.A., F.R.S. [Received November 8, 1887.] The genus Myosorex1 was founded in 1837 by Dr. J. E. Gray for the reception of a small species of white-toothed Shrew, Sorex varius, Smuts, from the Cape Colony ; which was then at once distinguished from all other known species of white-toothed Shrews by the short, subequal, and rather coarse hairs covering the tail. Trivial as this character may appear, and as such it has evidently been hitherto regarded by systematic zoologists, it is, however, the only one out of the many enumerated in the original definition of this genus (see footnote below) which is really characteristic of it taken in connection with the white colour of the teeth. MYOSOREX. Myosorex, Gray, Proc. Zool. Soc. 1837, p. 124. General characters those of Crocidura, but distinguished by the absence of long hairs on the tail, which is clothed with short fur of equal or subequal length, by the shortness of the third upper incisor, and by the absence of a distinct cloaca, the generative organs and the alimentary canal opening on the surface close together by distinct orifices. Dentition : Inc-a^^-" = 30 or 32 teeth. Range. Africa south of the Sahara Desert. 1. MYOSOREX VARIUS. Sorex varius, Smuts, M a m m . Capens. 1832, p. 8. Myosorex varius, Gray, Proc. Zool. Soc. 1837, p. 124. This, the largest species of the genus, is somewhat larger than Crocidura aranea. The body is clothed with dense fur, pale reddish grey on the surface, passing gradually into ashy beneath, the basal four-fifths of the hairs bluish ; tail clothed thinly with equal-sized reddish-grey hairs forming a small pencil at the tip. The lateral gland is well developed in males, rudimentary or absent in females, and situated close behind the arm. The teeth are very peculiar and characteristic. The upper incisors and premolars are provided with prominent basal processes, the third 1 " MYOSOREX, Gray. Head elongate, ears hid under the soft fur; tail elongate, slender, covered witb short, rigid, close-pressed hairs, when old quadrangular ; feet and toea not ciliated; teeth white; cutting-teeth |, two upper central unequally bifid, tbe second lateral moderate, the third very small rudimentary, the fourth small but larger than the third ; front lower cutting-teeth elongate, with an entire sharp upper edge ; second and third lateral teeth email, simple, crowded on the base of the front ones."-Gray, P. Z. S 1837 p. 124. 38* |