OCR Text |
Show 36 MESSRS. WATSON AND YOUNG ON THE [Jail. 14, twoparts-a smaller, lying to the left, and a larger irregularly quadrilateral mass, which lies to the right of the gall-bladder. The right hepatic segment, moreover, presents well-marked Spigelian and caudate lobes. These are quite continuous with each other, and extend along the posterior margin of the transverse or portal fissure. The gall-bladder, situated on the right central lobe, is of large size and regularly pyriform. The cystic duct is l^ inch in length, and unites with the left hepatic duct, which, after a farther course of half an inch receives the right hepatic duct. The common bile-duct, formed as described, enters the duodenum along with the duct of the pancreas. In respect of the liver, //. crocuta agrees closely with H. striata and H. brunnea, differing from the former, however, in the absence of the sharp curvature of the neck of the gall-bladder described by Daubenton1, and referred to by Meckel2. The resembance of this viscus to that of Proteles is no less striking, the only difference between them consisting in the more complete separation of the lobes in H. crocuta than in Proteles. Pancreas.-Measures one foot in length, and has an average breadth of one inch. It occupies the usual position. Spleen.-Elongated and tongue-shaped, measures 16 inches in length ; its borders are very irregular, but without distinct fissures. Its widest portion is 3, and its narrowest 1 inch in breadth. These measurements correspond closely with those of the organ in other species of Hycena. The viscus differs from that of Proteles3 only in its larger size and in the absence of any oblique fissure on its outer surface. Larynx and Respiratory Organs. Larynx.-The superior aperture of the larynx is guarded by an epiglottis of large size; its posterior surface is deeply concave, and its apex uniformly rounded. In respect of its form this structure resembles much more closely that of the Felidae than of the Canidae, in the latter of which it is distinctly triangular and almost flat. The thyroid cartilage is wide, and, as observed by Prof. Flower in Proteles, destitute of a fissure on its lower margin. It differs from the thyroid cartilage in both Felidae and Canidae in the much greater projection of its anterior tubercle. The cricoid cartilage is of the same general form as in Proteles, differing from the latter, however, inasmuch as its upper border posteriorly is not prolonged into a median pointed spine. In consequence of this the arytaenoid cartilages extend beyond the highest point of the cricoid, and are not situated below the level of its posterior median spine as is the case in Proteles. The false vocal cords (which, according to Mayer4, are absent in H. striata) are rounded and soft, and are placed very obliquely between the arytaenoid and thyroid cartilages, their anterior extremities being 1 Loc. cit. 2 Op. cit. vol. viii. p. 720. 3 Prof. Flower, loc. cit. 1 " Ueber den Ban des Organes der Stimme," Nova Acta Acad. Naturce- Curios. vol. xxiii. 1851, p. 694. |