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Show 4 MR. F. E. BEDDARD ON THE CRANIAL [Jan. 17, f believe that this extension forwards of the pterygoids and subsequent cutting off of the palatines from forming the median portion of the hard palate is a new fact so far as concerns the Lacertilia. It is at any rate clear that the fact, if known and on record, has escaped general attention. For in the elaborate account of the development of the skeleton of Hatteria by Prof. Howes and Mr. Swinnerton *, the greater part of the " Introduction " is devoted to emphasising the characters of the palate in Hatteria,from which introduction I extract the following sentences, viz. :-" One of its (i. e. Hatteria!s) most distinctive characters is the forward prolongation of the pterygoids to meet the vomers with apposition in the middle line. The mere forward prolongation referred to is a feature already recognisable among the Batrachia and Stegocephalia." The authors then proceed to refer to those reptiles and birds in which this forward prolongation with or without apposition occurs ; but they mention no Lacertilian in which this state of affairs exists. It is plain therefore that it is meant to contrast Hatteria with Lizards in the arrangement of the bones of the palate. I am thus able to record here a new (or at least little known and overlooked) morphological fact which has been held to be of considerable importance. It would thus appear that the peculiarities of the palate of Hatteria as distinguishing that reptile from the Lacertilia have been somewhat overrated, of course through ignorance of the conditions which obtain in the lizard which forms the subject of the present communication to the Society. Apart altogether from the new facts contained in the present paper, the difference between Hatteria and the Lacertilia as regards the palate is not greater than between the Emu and a Rail, and is, indeed, almost exactly the same so far as the point under discussion is concerned. The analogy may now, it will be observed, be pushed still further. Uromastix is Lacertilian so far as its general anatomy is concerned, but shows in its palate a likeness to Hatteria. just as the Tinamou and some other birds t are carinate in most features but " strutliious " in certain palatal arrangements. A " Rhyncho-cephalian " character of the bird palate, as Prof. Howes and Mr. Swinnerton term the thrusting forward of the pterygoids, has been shown to be transitory in some birds and subsequently lost through co-ossification. Whether this is the case with any true Lacertilia I am not aware. It must not be understood that I am arguing for a special likeness between Hatteria and Uromastix among the Lacertilia. I am only urging that a character supposed to be peculiar to Hatteria as contrasted with the Lacertilia is not peculiar to that reptile but is found in a Lacertilian. In regard to the palate there is another fact which requires * " On the Development of the Skeleton of tlie Tuatera," Tr. Z S xvi p 2 (1901). t See Pycraft, " Contributions to tlie Osteology of Birds," 1' . Z. S. 1898, p. 973. |