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Show 160 MR. ST. GEORGE MIVART ON MICRORHYNCHUS. [Mar. 13, les memes particularites; seulement le canal lacrymal est moins avance dans la face et presque marginal ; les orbites sont plus grandes, l'incisif est encore plus petit, et la machoire inferieure a son angle plus large, plus arrondi, et sa symphyse plus longue et plus oblique." Fig. 6. Front view of skull. Scale, nat. size. One of the most striking characters of the skull of M. laniger is the exceeding shortness of its facial part, which distinguishes it from all other Lemuroidea, with the exception perhaps of Tarsius and Cheiromys. As in Tarsius and some Galagos, the antero-posterior extent of the anterior opening of the orbit greatly exceeds the length of the muzzle in front of it. When viewed from above, the entire skull is seen to be broadest between the outer margins of the orbits ; but the greatest width of the cranium proper is in a line drawn just behind the posterior ends of the zygomatic arches. As in Indris the mastoidal region of the periotic is not inflated, but there is a prominence at, and above, the posterior root of each zygoma just above the aperture of the external auditory meatus. This peculiar enlargement is absent in Indris and in all the other genera of Lemuroidea; but when compared with some of the smaller species of the suborder (as the Nycticebinar and Galagonina) it seems to answer to their mastoidal swelling, only placed further forwards. The surface of the cranium presents a strongly marked depression (concave both antero-posteriorly and transversely) between the orbits; behind this the roof of the skull is smoothly and evenly convex, except a slight concavity just in front of the most anterior point of the supraoccipital. There appears to be no interparietal. The two temporal ridges are slightly but distinctly marked. As in Indris, they do not unite to form a sagittal ridge, which is the case in Hapalemur, and sometimes in Galago. The nasals are rather strongly convex, and are broader at each end than in the middle, instead of narrowing gradually upwards as in Indris. They are shut out from the lachrymal by a narrow process of the maxilla which ascends to join the frontal, the short fronto- |