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Show 410 MR. G. BUSK ON FOSSIL REMAINS FROM BORNEO. [JunclO, failed him, and that the two teeth arc those of the Rhinoceros, and the single one that of the Ruminant in question. The Rhinoceros-teeth are the right and left second upper molars (m. 2), evidently belonging to the same individual. They consist only of the crown portions, which appear to be not fully developed at the base, and are wholly in the " germ " state, having no fangs and never having been protruded from the alveolus ; they amply suffice, however, to afford distinctive characters. -\s regards the condition in which they are, the enamel and dentine, so far as the latter can be seen here and there, are extremely brittle and obviously contain but little animal matter. The surface is of a deep brown colour, and the subjacent substance has also a strong ferruginous tinge ; it is also, as shown by experiment, strongly impregnated with iron. There is no dendritic appearance in any part When wetted they exhale a remarkably strong peaty or earthy odour. These circumstances prove that they have lain for a long time in soil containing much iron and vegetable matter, and probably of a peaty nature. The hollows of the teeth, moreover, were partially filled with mould having the above characters. It may consequently be concluded from this, and from the entire absence of anything like the usual cave-earth, that the teeth had in all probability been lodged in a dried-up bog or peaty marsh, and not in a cavern-a conclusion which is in accordance with the statement of Signor Beccari above cited. They must be regarded as fossilized in the same sense as the usual remains found in quaternary deposits of a similar kind, though it is impossible, in the absence of other data, to express any opinion as to the probable period they had been so imbedded. Before proceeding to describe the morphological characters of the teeth, it will be as well to premise a few words in explanation of the terms employed. The upper molars of Rhinoceros are of a more or less quadrilateral form, and are almost always rather wider in the transverse than in the longitudinal or antero-posterior direction. They present, therefore, four sides-an external or dorsal (the dorsum), an internal, an anterior, and a posterior. They may also be described as consisting of an external wide lamina, which forms the entire outer side of the tooth, and from which project obliquely, inwards and backwards, two transverse plates which, on the inner aspect, end in two conical or pyramidal columns or pillars. These columns and plates are sepa-tated from each other by a wide and deep valley, the median sinus: and in front of the anterior column, towards the inner part, there is in most cases a shallow valley, the anterior sinus, and behind the posterior column a much deeper one, the posterior sinus. On the dorsum may be observed, besides the anterior and posterior margins, which are very usually more or les3 elevated, three vertical elevations or costee, of which the anterior is always by far the most prominent. On the anterior face the anterior sinus is crossed at the bottom by a prominent ridge, the anterior vallum; whilst the posterior sinus, on the opposite side of the tooth, is closed in behind by the |