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Show 1904.] TRIASSIC REPTILE TELERPETON ELGINENSE. 473 suture between ' squamosal' and ' quadrate,' and in the exaggerated length of the anterior mandibular tooth, owing to the root being made to project beyond the bone, the thecodont nature of the Reptile not having been recognised. As to the side teeth, Huxley only described them from their lateral aspect, without mentioning that on the right side of the specimen the fourth maxillary tooth may distinctly be seen, in a transverse section, to have been transversely expanded and molar-like. The skull is seen on Mr. Taylor's specimen (B) from the East Quarry, Lossiemouth, to have been much depressed, about as long as broad, obtusely pointed in front, with enormous pear-shaped orbits separated from the posterior border by a narrow supra-temporal roof; these orbits are twice as long as broad, and twice as broad as the least interorbital width, which equals the least width of the supratemporal roof. The nasal bones are large, sub-triangular, and the nostrils nearly terminal. All the bones are paired, and the sagittal suture is interrupted by a very large, round pineal foramen, which, instead of being bordered entirely by the parietal bones, as in Procolophon, is situated between the frontals and the parietals. The posterior part of the upper surface of the skull and the interorbital region are also well shown by the imperfect skull, C. The posterior outline of the skull is strikingly as in Procolophon, there being a shallow notch in the posterior border on each side, and the supratemporal (epiotic of Seeley, squamosal of A. S. Woodward) forming a pointed process above the deep lateral notch which probably formed the border of the large auricular meatus. Xo vacuity could be detected representing a latero-temporal fossa. The annexed restoration of the upper surface of the skull is based on Mr. Taylor's two specimens, some of the sutures, in dotted lines, being hypothetical. A n accident to specimen B, in the course of preparation, has resulted in the fortunate exposure of a part of the dorsal aspect of the palate, which is seen to have been extremely similar to that of Procolophon, at least so far as the basisphenoid and the pterygoids are concerned, but the vacuity between these three bones was broader than long, instead of longer than broad, I can see no trace of a parasphenoicl, any more than in the specimen of Procolophon described by Seeley *. Each maxillary bore six large bilobate teeth, the roots hourglass-shaped in horizontal section, their transverse diameter at least double the longitudinal, and with large pulp-cavities; the teeth were implanted in sockets, not acrodont as believed by Huxley. Three conical teeth were present in each pra?maxillary, the first the largest. The circular roots of a few vomerine teeth are visible in specimen 0. The dentition therefore bears a close resemblance to that of * On the skull of Procolophon, cf. Seeley, Phil. Trans, clxxx. B, 1889, p. 269, pi. ix.; A. S. Woodward, Vert. Palseont. p. 148, tig. (1898); Broom, Rec. Albany Mus. i. 1903, p. 9. |