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Show 430 MR. W. A. FORBES ON THE AFRICAN ELEPHANT. [May 6, but quite impermeable. The aorta gives off an innominate artery, which is only an inch long and then divides into right brachial and right and left carotids. The left brachial is given off immediately after the innominate. This agrees with the descriptions of E. indicus as given by Hunter, Owen, Vulpian and Philipeaux, Watson, and Miall and Greenwood. On the other hand, Cuvier and Mayer found three trunks, namely two brachials and a common carotid. I found no " arteria thyroidea inferior simplex " coming off from the point of division of the two carotids, such as is figured by Mayer (I. c. pi. 11. fig. 3) and Watson (Journ. Anat. & Phys. vi. pi. vi. fig. 1). The weight of the heart and great vessels, cut sbort and cleaned of blood, was 7 lb. There was no os cordis ; and the same was the case in Perrault's specimen; nor is any such bone recorded in E. indicus by recent anatomists. Respiratory System.-The lungs were very simple in form, each lung being undivided and bluntly triangular in general outline, the left being shorter and broader. In the undistended state they measured as follows :-Right lung 23 inches long by 12 broad, left 21 inches by 14. I found no accessory lobe on the right side, such as has been observed by some anatomists in E. indicus. There is no extra bronchus. The trachea is short, measuring about a foot in length, and not quite two inches in external diameter. It is composed of 28 rings, which are nearly complete, leaving hardly any space behind between their ends. They vary considerably in size in different parts of their circumference. The first three rings, as in E. indicus, are truncated obliquely behind, the space so formed being covered in by the body of the cricoid cartilage. The larynx (fig. 6, p. 431)"_is of considerable size. The epiglottis, when covered by its soft parts, is short, thick, and rounded. The thyroid consists of two rhomboidal wings, 4 inches long, and 3\ deep, which are united in front superiorly for about one inch, the deep and narrow notch left between the remaining part of the wings being filled up by connective tissue. The superior cornua are short and scarcely project. The posterior are about one inch long, and are directed downwards and forwards in close proximity with the body of the thyroid cartilage, to which they are attached by connective tissue. Tbe postero-inferior angle of the thyroid cartilage also develops an articular facet; and this is enclosed with that of the posterior cornu, in the common capsule of the crico-thyroid articulation. The cricoid (see fig. 6) is of the usual type. Its anterior part is 1 inch deep, the posterior (somewhat pentagonal) part 2 inches. The processes for articulation with the thyroid stand out in a step-like way, and are more or less clearly divided into two facets, corresponding to the double articulating surfaces of the thyroid. The arytaenoids (see fig. 6) are vertically elongated. Each measures about 2\ inches long by \\ broad. They have a conspicuous, vertically directed, raised spine-like process, and a large notch behind the supero-posterior angle. The cartilage of each side articulates with its fellow both above and below this notch. The processus vocalis is short and blunt. The true vocal cords are well-marked |