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Show 1879.] MR. GARROD ON THE ANATOMY OF HELICITIS. 307 border of the temporal lobe (X). The crucial fissure is long and oblique, and situated further back than usual." In the footnote (J) we read, " Except in the smaller numbers of the genus 31ustela, where the sulcus separating the superior from the middle gyrus is less produced posteriorly than in others of the group. In Galictis vittata, however, the brain is quite a miniature of that of a Bear; but the middle convolution is united with the upper one at its superior anterior angle. Fig. I. Brain of Helictis subaurantiaca; superior aspect. Fig. 2. Brain of Helictis subaurantaica; lateral aspect. In Helictis, as also in Lctonyx zorilla, the superior gyrus ceases at the superior posterior angle of the hemisphere, as in Mustela. The anterior limb of the inferior gyrus is extremely narrow, especially near its upper end, where it becomes almost hidden by the corresponding part of the posterior limb of the same gyrus. A. small sulcus tends to divide the transverse part of the middle gyrus from its posterior limb. Most peculiarly, in Helictis there is no crucial fissure, because the hippocampal gyrus appears upon the superior aspect of the brain. This is the case in no other carnivorous animal with which I am acquainted, but occurs in 3Ioschus, Cervus pudu, and other smaller Ruminantia. 20* |