PROF. OWEN ON THE ANATOMY OF THE INDIAN RHINOCEROS. 47 
There was no trace of a valve at the orifices, either of the inferior cava or coronary 
vein; the latter easily admitted the end of the fore-finger. In the right ventricle, the 
tricuspid valve presented the following attachments :—its strong chorde tendinez were 
distributed to three obtuse and transversely oblong columnz carnez, one rising from the 
external or moveable wall, a second from the septum, and a third smaller one from the 
anterior interspace between the fixed and moveable wall: the tendons diverged from 
each column to the two contiguous moieties of the divisions of the tricuspid valve; a 
provision which ensures the simultaneous action and the outstretching of these three 
membranous processes. There were besides two smaller columns placed opposite to 
each other, one on the free and the other on the fixed wall of the ventricle ; they were 
connected together by a single strong tendon passing across the ventricular cavity from 
the apex of one to that of the other. 
The mitral and semilunar valves offered nothing unusual. 
The aorta, after giving off two coronaries, each of which freely admitted the fore- 
finger, ascended and divided at the summit of its arch into the descending aorta and 
a smaller trunk supplying the head and anterior extremities. The vessels immediately 
derived from the ascending division were the two internal thoracics', the brachials, and 
the common trunk of the two carotids. 
Each lung was divided into a small upper and a large lower lobe ; the right lung gave 
off in addition a transversely elongated narrow azygos lobe. The superior lobe of each 
lung was characterized by numerous deep marginal notches, which gave it an appendicu- ~ 
lated character. The lining membrane of the branches of the bronchiz presented very 
strongly marked longitudinal ruge ; that of the trachea was similarly disposed. After 
reflecting the pleura from the surface of the lung, a thin extensible stratum of condensed 
cellular tissue continuous with the interlobular cellular tissue could alone be perceived. 
Between the pleure and the parietes of the chest was much elastic tissue. 
The cartilaginous hoops of the trachea are stout and close-set ; they meet posteriorly, 
but their extremities do not coalesce; their number was 31. The diameter of the 
windpipe is two inches and a half, being not greater than that of the Lion. 
The larynx consists of the thyroid (Pl. XV. th), cricoid (Ib. c), and arytenoid (Ib. a) 
cartilages, of the epiglottis (Jb. e), and of a small sesamoid fibro-cartilage (Jb. fig. 1, k) 
developed in the commissure of the ‘ arytenoidei transversi’ and ‘ obliqui,’ here blended 
together; but there is no trace of the cartilages of Santorin or Wrisberg. The wings 
of the thyroid cartilage meet at a slightly obtuse angle, contrary to their usual dis- 
position in the Hog tribe and Ruminants: there is no notch at the upper margin of 
the anterior median line; but there is a considerable triangular vacancy below, filled 
1 The intercostal spaces above or anterior to the heart, are numerous in proportion to the narrowness of the 
chest, which obliges the heart to be placed nearer the diaphragm; and the internal thoracics, which are of insig- 
nificant size in Man, are there largely developed in order to supply those intercostal spaces, which, from the 
position of the heart, cannot receive their arteries directly from the trunk of the aorta. 
VOL. IV.— PART II. I 
