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Show the inner edge of the quadrate (qu.). The quadratojugal is in contact with the quadrate only at its lower end, thus leaving a rather large postero-temporal vacuity (ptv.) which is especially well seen on the left side. The complete occipital region, as here interpreted, is shown in the accompanying restored sketch (text-fig. 34, p. 172). It obviously conforms much more closely to the Amphibian type than to the arrangement in any known reptile. It therefore agrees with the evidence derived from the palate and the supratemporal plates, showing that the Labyrinthodonts are Amphibia. The characters of the cranial roof, the anterior end of the palate, and the teeth, prove that the skull now described belongs to the genus Capitosaurus. It cannot, however, be referred to any of the known species of this genus. It differs from the skull of the type-species, C. cirenaceus, from the Keuperof Franconia*, in the narrower and more tapering form of its rostral region, the more elongated shape of the orbits, and its more nearly circular pineal foramen. It is distinguished from the skulls of C. nasutus t and C. robustus +, among other characters by the slighter excavation of its occipital border and by the shape of the outer pair of its supratemporal plates. It is also distinguished from the imperfectly known skull of C. fronto § by the different shape of its auditory notch and the coarseness of its external ornamentation. The new specimen therefore represents a hitherto unrecognised species, which may be named G. stantonensis. 1904.] LABYRIXTIIODONT SKULLS. 173 II. A p h a n e r am m a rostratum, gen. et sp. nov. (Plate XII.) The imperfect Labyrintliodont skull from Spitzbergen was found by Profs. J. W. Gregory and E. J. Gar-wood in the Trias of Sticky Keep, associated with a few short and deep, biconcave vertebral centra, which probably belonged to the same animal. It is broken into five pieces, which show little beyond impressions of the bones. Three fragments are internal moulds, while the other two pieces bear' marks of the exterior. The right half of the postorbital region and the middle portion of the rostrum are missing. Enough, however, is preserved to indicate that the skull must have been of a much elongated shape, with a slender snout. It is very little depressed behind, and the occipital plane slopes backwards. Its external surface was ornamented with large reticulating rounded ridges, which were sometimes inter rupted, as shown by the impression of part of the left cheek * Graf zu Munster, Neues Jahrb. fur Min. 1836, p. 5 8 0 ; H. von Meyer, ‘ Die Saurier des Muschelkalkes ' (1847-55), p. 152, pi. lix. figs. 5-7. f H. von Meyer, Palaiontogr. vol. vi. (1858), p. 222, pis. xxiv.-xxvi. + H. von Meyer, ‘ Die Saurier des Muschelkalkes ' (1847-55), p. 146, pi. lix. figs. 1-4, pi. lxi. fig. 10. Cyclotosaurus robustus, E. Fraas, Palseontogr. vol. xxxvi. (1889), p. 121, pis. ix., x., pi. xi. figs. 1-4. § H. von Meyer, Palajontogr. vol. vi. (1858), p. 229, pi. xxvm. fig. 2. |