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Show 534 DR. C. J. FORSYTH MAJOR ON A LEMUROID SKULL. [June 20, margins of the right and left external auditory meatus across upper surface of the skull. In the fossil this part of the superior outline of the skull is nearly horizontal, so that the anterior portion of the interparietal appears almost on the same level with the highest region of the parietals. The flattened posterior moiety of the interparietal slopes suddenly down to the occipital crest; the occiput proper is almost vertically truncated, much as in the skull of Mycetes. On the other hand, in Hapalemur, as in existing Lemuroids Skull of fossil Lemuroid. Side view, two-thirds nat. size. generally, the occipital crest has a more oblique direction, its inferior edge being considerably more in advance of the upper one ; and the whole occiput partakes partly of this same direction. The inferior margin of the postorbital frontal processes is cuttingly sharp in the Malagasy fossil; this is also characteristic of Hapalemur (both H. simus and H. griseus). In the former the frontals extend laterally somewhat farther backwards than in the latter; and the postero-superior margins of the postorbital processes continue backwards in the shape of two sharp crests, which unite at the coronal suture. No sagittal crest is visible on the median line of the parietals, which are as yet separated; but it appears obvious that this would be the case in a more aged specimen. In Hapalemur, even in adult specimens, no such elevated frontal crests are developed, and instead of a sagittal crest there are two temporal ridges remaining low and separated anteriorly, although near the interparietal they converge to form a feeble median crest. The interorbital region is absolutely broader in Hapal. simus, and is, besides, vaulted from before backwards and from right to left, owing to underlying frontal sinuses. These last are not entirely absent in the fossil, as seen in the inferior broken portion; they extend even partly into the postorbital processes. The olfactory fossa appears very large in the fossil, as is the case in Lemuroids generally. The anterior end of the cribriform plate is but slightly more elevated than the posterior; this is the |