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Show 1905.] ON THE ANATOMY OF THE FERRET-BADGER. 21 2. Some Notes upon the Anatomy of the Ferret-Badger, H e l i c t i s p e r s o n a t a . By F r a n k E. B e d d a r d , M .A., F .R .S ., Prosector to the Society. [Received March 21, 1905.] (Text-figures 7-12.) The dissection of a female example of Helictis personata, which was acquired by the Society on the 4th and died on the 14th November, 1904, enables me to lay before the Society some new facts in the anatomy of this genus of Carnivora. So far as I am aware, the only zoologist who has investigated the anatomy of the soft parts of the genus Helictis is the late Prof. Garrod whose memoir deals with the essentials in its structure. The species examined by him was Helictis subaurantiaca. It is not therefore unnecessary to report upon the anatomy of another species, though the differences between the two are, as might be expected, but slight. I deal, moreover, with a few points upon which Prof. Garrod did not touch in his account. § Brain. The brain of Helictis subaurantiaca has been described and figured (in dorsal and lateral view) by Prof. Garrod in his memoir already referred tot. The figure of the brain of Helictis personata submitted herewith (text-fig. 7, p. 22) shows certain differences, which I regard as worthy of record in view of the little knowledge which we possess upon the matter. The most salient difference which this brain shows from that of //. subaurantiaca is the very slight appearance upon the dorsal surface of the intercalary prolongation of the calcarine sulcus. This furrow, as will be seen in the figure (text-fig. 7), only appears dorsally for a short distance quite at the posterior end of the hemispheres, and also of course anteriorly where the two sulci join the crucial sulci. The precrucial sulcus in my specimen is not so fully developed, particularly upon the left side (text-fig. 7, Pc.S'.), as in Garrod's specimen of Helictis subaurantiaca. It does not entirely delimit the ursine lozenge in front. The Sylvian fissure on both sides of the brain joins the supra-svlvian, tlie gyrus anterior to the Sylvian being apparently depressed below the surface of the hemispheres. There is a hint of this in Garrod's figure, but hardly in that of Dr. Elliot Smith, though it refers, I imagine, to the same brain. The remaining fissures agree absolutely with those of Helictis subaurantiaca. I pass on therefore * " Notes on the Anatomy of Helictis subaurantiaca," P. Z. S. 1879, p. 305. f This brain is also figured in the Catalogue Physiol. Series Roy. Coll. Surgeons, vol. ii. (2nd ed.) p. 273, by Dr. Elliot Smith. |