Since describing the skull of Anthracotherium Gresslyi (= Hyopotamus Gresslyi. Rüt.) in the last Number of the Magazine (p. 63), I have observed that the right maxilla of a small anthracotheroid from the Upper Eocene “Bohnerz” of Canton Vaud, Switzerland, has been figured by Pictet in his “Matériaux pour la Paléontologie Suisse—Vertèbres de la Faune Eocéne, Supplement, pl. xxiv. fig. 5,” under the name of H. Gresslyi. The British Museum has recently acquired some upper true molars from the same formation agreeing precisely with those of Pictet's specimen; and a comparison of these teeth with those of the Brit. Museum specimen of A. Gresslyi (figured in my memoir already quoted) shows that they are quite different;— being distinguished by their slightly inferior size, the more inward inclination of the outer surfaces of the external columns, as well as the more distinct loop connecting these columns. These teeth agree, in fact, with those of brachydont species of Hyopotamus, like H. porcinus. Pictet's figure also shows that his specimen differs from Anthracotherium Gresslyi in having an elongated, instead of a triangular Pm. 3.