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Show 1878.] MR. A. H. GARROD ON TOLYPEUTES TRICINCTUS. 227 tremity. It does not, therefore, turn round the posterior end of the hemisphere to become continuous with the fissure of the hippocampus, as it does in Dasypus sexcinctus. Anteriorly it ceases in the middle of the superior surface of the frontal lobe, a short distance behind the convex margin of its upper moiety, and at about the transverse level of the ends of the anterior sulcus. The general direction of this sulcus is horizontal when viewed from the side, it being slightly curved, with its convexity downwards. The sulcus present on the superoparietal cerebral surface of Dasypus sexcinctus is entirely absent in Tolypeutes tricinctus. The internal cerebral surface very closely resembles that of Dasypus sexcinctus as figured by Prof. Turner. The corpus callosum is short, pointed in front, inclined obliquely upwards and backwards, being rounded and thick posteriorly, where it becomes continuous with the psalterium of the fornix. The anterior commissure is well developed. The sides of the corpus callosum are very much upturned. The calloso-marginal sulcus is feebly represented, being of about the length of the corpus callosum, and situate at a level a little anterior to it (vide fig. 2, d). The corpora quadrigemina are large, and separated by a deep longitudinal fissure, the pineal gland being extremely small. In the natural position of the spirit-preserved specimen it was quite impossible to cover the testes by the posterior margins of the cerebral hemispheres, which leads me to think that Prof. Turner is hardly justified in his correction of Tiedemann, Cruveilhier, and Stannius, who all say that the corpora quadrigemina are uncovered by the cerebrum (in part at least) (vide fig. 2 a). The median and lateral lobes of the cerebellum are nearly equal in size. The medulla is very large, and the fifth nerve is enormous. The optic nerves and commissure are insignificantly small. I could not see any corpora albicantia. With reference to the visceral anatomy of Tolypeutes tricinctus, the tongue was 2 | inches long in my specimen, and *4 inch broad at the base. It is soft and elongate-triangular (lanceolate) in shape, flattened above. No circumvallate papillse are visible, the others being inconspicuous and uniformly distributed. On the palate there are nine larger and smaller transverse ridges on each side, the interval between the last pair of molar teeth being smooth. The number of teeth is eight above and seven below, on each side. The epiglottis is slightly indented by a notch in the middle line; and the soft palate embraces it, so that the rima glottidis opens into the posterior nares, as in so many mammals, during ordinary respiration. A tonsilitic pit exists on each side of the fauces. The lungs are divided into four lobes on the right side, and two on the left. In most Dasypodidse there are three lobes on tbe left side; but in the animal under consideration the two upper were blended. Three is said by most authors to be the number of lobes of the right lung ; but I always find a fourth azygos lobe as well, hidden behind the heart, in the genera Dasypus and Xenurus, absent in Tatusia. Dr. Murie's figure of the lungs scarcely differs, ex- |