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Show 1871.] MR. ST. GEORGE MIVART ON HEMICENTETES. 63 premolar in front of it, it is much antero-posteriorly extended, i. less canine-like. The third premolar is nearly contiguous to the second ; it is much simpler than is the homologous tooth in Centetes. The principal cusp predominates less over the talon; and sometimes there is a minute cusp in front of the principal one. The tooth is as it were formed entirely of the cingulum, there seeming to be nothing answering to the normal principal cusps, still less to any internal cingulum. Nevertheless it is probable that the actual principal cusp is really made up of the normal external cusps, plus the cingulum, fused together. The first and second upper molars are similar to the last premolar, except that the part answering to the normal cusps is more developed, and extending inwards, most so in the more posterior tooth, and showing that the principal cusp of the third premolar is (as before stated) probably of similar nature. The external cingulum develops two low subequal cusps. There is no internal cingulum. The third and last upper molar is less in antero-posterior and very much less in vertical extent than is the tooth in front of it. Also the cingulum bears a smaller proportion to the rest of the tooth, which thus comes to consist of two subequal parts, one exterior, the other internal. All the molars are contiguous to each other and to the third premolar. In the lower jaw the six incisors are much closer together than are those of the upper jaw. This is less due to their implantation than to the lateral expansion of their crowns. They are less ver-tinally extended than are the upper ones, and each expands upwards from the root to the cutting-edge. Fig. 5. Teeth of lower jaw, four times the size of nature. The canine is very much smaller, relatively as well as absolutely, than in Centetes. It is not received into any fossa in the upper jaw. It is a much curved conical tooth, with a considerable posterior cusp at its base. The first premolar, in size and shape, is quite like the canine in front of it. It is separated from the latter by a considerable interval. The second premolar is quite like the first lower premolar of Centetes. In consists of three unequal cusps, without any internal production. The middle cusp is much the largest, and curved and pointed like the principal cusp of the first premolar. The third premolar projects inwardly hardly, if at all, more than |