| OCR Text |
Show 158 BR. E. LONNBERG ON THE [Feb. 20, the incisura thyroidea superior. In Capra the corresponding relation is only 1 to 1|, and in Capreolus I have found a similar condition. Cornua superiora in the Musk-ox are not so much elongated as, for instance, in Cervus elaphus and Capreolus, in which they are larger than the cornua posteriora, but of comparatively the same size as in Bos and Capra. They are directed dorsally, so that their direction forms a nearly right angle against the longitudinal diameter of the larynx, and is not parallel to the same as in Capra and Bos. The cornua inferiora are very long and arcuate. As a result of the great development of the cartilago thyroidea in Ovibos, the longitudinal diameter of the dorsal part of the cartilago cricoidea, which in Capra, Cervus, and Capreolus exceeds the length of the cartilago thyroidea, only equals 72 °/0 of the length of the first mentioned cartilage. In Bos the anterior portion of the cartilago thyroidea is enlarged as in the Musk-ox, so that the length of the larynx exceeds the dorsiventral diameter, but the length of the cricoidea equals or nearly equals the leugth of the thyroidea along the anterior keel. Thepomum aclami is less developed in Bos than in Ovibos, and the distance from tbe same to the insertion of the cornua posteriora exceeds the length of the thyroidea in Bos and still more so in Capra; but in Ovibos this distance is not much more than | of the length of the thyroidea, although the pomum adami is so much protruding. This indicates that the lateral extension compared with the length of the thyroidea is much less in Ovibos than in Bos. This can be seen in the figure. On the whole there is, however, more resemblance with regard to this organ between Ovibos and Bos than with the others. The epiglottis of the Musk-ox is strongly recurved at the apex, but blunt (nearly rounded). It thus makes a less triangular impression than that of Capra, Bos, &c. The plica ary-epi-glottica is well developed, although not so much, it seems, as in Ovis and Capra. The basal part of the epiglottis is strongly developed and reaches the same length as the free portion. On the sides it is well curved so as to embrace the arytenoid cartilages. The trachea is very wide and has a peculiar shape. It is flattened dorso-ventrally, so that the transverse diameter of its Fig. 11. Tracheal ring of the Musk-ox. lumen is 5 cm., but the dorso-ventral only 3 cm. This is effected by the tracheal rings (fig. 11) not meeting dorsally, but leaving a |
