158 DR. E. LONNBERG ON THE [Feb. 20, 



the incisura thyroidea superior. In Capra the corresponding 

 relation is only 1 to lg, 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 compara- 

 tively 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 °/ 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 length of the thyroidea along the anterior keel. 

 Thepomurn adami is less developed in Bos than in Ovibos, and the 

 distance from the same to the insertion of the cornua posteriora 

 exceeds the length of the thyroidea in Bos and still more so in 

 Capra; but in Ouibos 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 he 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 Copra, 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 car- 

 tilages. 



The trachea is very wide and has a peculiar shape. It is flat- 

 tened 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 



