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Show 1895.] LORIUS FLAVOPALLIATUS AND PSITTACUS ERITHACUS. 375 and at its preaxial end sends forwards a sharply projecting anterior palatine process (see p. 378, figs. 6 & 7, two processes behind the end of the line running inwards from the letters sp). Behind this attachment it descends backwards with a slightly irregular margin in P. erithacus, which runs on into that of a strongly-marked posterior palatine process (fig. 2, pp). In L. flavopalliatus this part of the postero-superior margin is still more irregular, presenting two blunt processes, one behind the other, aud projecting dorsad and postaxiad almost at right angles to the general trend of the palatine. There is, however, only a very minute posterior palatine process (fig. 1, pp), which projects from behind the base of the more posterior of the two marginal processes just mentioned. The antero-superior margin is, in both species, strongly concave, with a foramen (for) opening a little behind its middle portion. Tbe antero-inferior margin of the palatine is elongated, slightly concave, and somewhat thickened and rounded in P. erithacus. In L. fiavopedliatus it is relatively, as well as absolutely, shorter, much more concave, and less thickened and rounded. The postero-inferior margin of the bone is the shortest of all in both species, and is strongly concave postaxiad; but in L.flavopalliatus this concavity is mainly produced by tbe prominence of the rounded angle between anteroinferior and postero-inferior margins of the bone, while in P. erithacus it is chiefly owing to the great extension backwards of the long and pointed posterior palatine process, which, as before said, is but a minute process in L. flavopalliatus. On the outer surface of the palatine two ridges run, in both species, postaxiad and ventrad, diverging backwards from the base of the anterior-palatine process, the inferior ridge (p) going to that of the posterior palatine process. Ventrad of the lower of these two ridges, the surface in L. flavopalliatus is convex in both directions for most of its anterior half, and concave (especially dorso-ventrally so) for slightly more than its posterior half (fig. 1, p). In P. erithacus this convexity is hardly to be traced, while the concavity just described is less marked. The most dorsal portion of each palatine is inflected mesiad, and so is much hidden when the cranium is viewed laterally, and can be best perceived when the ventral and inner surface is looked at (figs. 6 & 7). The higher of the above-mentioned two diverging ridges coincides with the line of inflection. The inner surface of the palatine will be noticed when the cranium as seen on its ventral aspect is described. The divergences, as regards the angles formed by the margins of the palatine with each other, are given after the list of cranial dimensions. In both species the pterygoid (pt), thus laterally viewed, is a slender bar of bone of equal breadth save that it expands slightly at its articulation with the quadrate. It appears below the zygoma in P. erithacus, diverging from it very slightly ventrad and post- |