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Show 352 DR. ST. G. MIVART ON THE ARCTOIDEA. [Apr. 21, internal the hinder one is very small. The fourth lower premolar has one principal cusp, with a minute one at its base in front, and two considerable-sized ones attached to it behind. These accessory cusps are larger than they are in the Dogs, and especially the one behind the principal cusp is more equal to the latter than it is in them. The first inferior true molar is not at all sectorial. _ It has two inner and two outer cusps and another (fifth) antero-internal cusp. The hindermost internal cusp may be subdivided into two smaller ones. Although this tooth is much like the corresponding one of the Civet, only the antero-external and the antero-internal cusps do not preponderate in height as in that animal. The two hinder cusps (one internal, the other external) correspond with the " heel" of the dog's tooth, while the more anterior part corresponds to the whole of the crown of the corresponding tooth of Felis. This "heel" in Procyon forms nearly half the tooth, and rises nearly as high as does the more anterior portion. It is very like the same tooth as it may be seen in Paradoxurus. The second lower true molar is quinquecuspidate like the first, only the azygos cusp is placed behind, instead of in front of, the two pairs. It is an exaggeration of the same tooth as found in Paradoxurus, but is more equal in size to the tooth in front of it. The muscles have been described by Dr. Harrison Allen *. The tongue is medially grooved at its anterior half and provided with a lytta which is relatively a little longer than in the Cats. The tongue is covered with small conical papillae, and fungiform papillae are scattered amongst them. The flattened papillae are moderately developed. There are ten, twelve, or fourteen rather small circumval-late papillae in two rows forming an acute angle open forwards, with five, six, or seven in either row. The descending aorta, after giving off in front its inferior mesenteric artery, gives off, on either side, an external iliac artery, aud a little beyond divides into two internal iliacs, from the bifurcation of which a small mid sacral artery continues on to the tail. The arch of the aorta gives off one great innominate artery, one left subclavian. The lungs are as usual in the Carnivora. The kidney has a single mamilla. The intestine in one instance presented a singular and very exceptional and elongated dilatation between the small and large intestine. This was in no wise in the form of a caecum, but merely a dilatation of part of the course of the intestine. The liver has its right half, rather, or very much, the larger. The left central lobe is simple and rather, or very, small. The bladder appears on the diaphragmatic aspect, through a perforation or a notch. The caudate lobe is moderate, and the Spigelian small. That part of the right central lobe which is on the left side of the bladder, is deeply furrowed. It has the pair of simple anal glands usual in the Carnivora. The bone of the penis is very large ; and in one instance the vasa deferentia opened upon the dorsal aspect of the urethra. 1 See Proc. Acad. Nat. Sc. Philadelphia, 1882, p. 115. |