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Show 146 ME. F. E. BEDDAED ON THE [Feb. 19, that of Gervais1, who represents the brain of this animal as comparatively complicated. As I have examined two brains which agree with each other, I think it may be fairly assumed that my description is accurate. § The Brain of Galago crassicaudatus. (Fig. 4.) The brain of this Lemur differs in several particulars from the brains of other Lemurs which I have examined, though it is constructed upon the same general plan. The general outline of the brain is much as in the genus Lemur. The fissures are, on the whole, few, when the size of the brain is taken into consideration, but some of them are very deeply engraved. This is the case with the Sylvian and angular fissures, which are really the only well-marked ones. Brain of Galago crassicaudatus. A, front, B, side -view. Lettering as in fig. 1. The Sylvian fissure is not quite so long as it is in some other Lemurs. The angular fissure is not more than a quarter of an inch long, but it is very deep ; it is slightly crescentic, the concavity embracing the extremity of the Sylvian fissure. The infero-frontal fissure on each side is represented by two detached portions, which are very short but fairly deep. Tbey are in the same straight line, and the direction is obliquely inwards as in the genus Lemur. There is a small dent in the brain-substance just on a level with the hindermost extremity of the infero-frontal sulcus, in the middle of the widest part of the sagittal gyrus, which appears to correspond to a more strongly marked impression that I have already referred to as existing in a similar position in the genus Lemur. Below the infero-frontal sulci is a rather faintly marked furrow, longitudinal in direction, which I compare 1 Loc. cit. fig. 2, pi. ii. |