1875.] PROF. W. H. FLOWER ON THE MUSK-DEER. 165 
Fig. 3. 
Epiglottis and opening into larynx, natural size. 
The thyroid body is much flattened and oval and of very loose 
texture, extending from the top of the first tracheal ring to the bottom 
of the eighth, 0''"8 long and 0!'-4 across at the thickest part. 
The number of rings in the trachea, above the part where the 
branch to the upper right lobe of the lung is given off, is 49, 
between this branch and the bifurcation 11; total 60*. Some of 
the rings are single at one side and bifurcated at the other ; thus the 
third ring is single on the left and double on the right side, and the 
succeeding ring has the opposite arrangement. These double rings 
have been counted as two in the enumeration given above. 
Thoracic Viscera. 
The hinder margin of each lung is entire. The lower lobes are 
nearly equal in size (the left. slightly the largest), of the usual trian- 
gular form, being divided off from the rest of the organ by a nearly 
horizontal fissure, which does not extend quite to the root of the 
lung behind, though further on the right than the left side. Near 
the upper part of the inner border of the right lobe, attached by a 
narrow neck, is the so-called “ azygos lobe”’ (fig. 4, 4) deeply fissured 
on its anterior surface. 
Above the horizontal fissure the arrangement on the two sides is 
very different. On the right side there are two distinct lobes, the 
cleft between them extending almost to the root of the lung; the 
upper one (R UV) roughly triangular, with the apex upwards and sup- 
plied with air by the upper branch of the trachea. It is constricted 
across its middle into an upper and lower portion. The lower one, 
or middle right lobe (R M), is tongue-shaped, with its apex directed 
forwards, and while connected at its base with both the upper and 
lower lobes, it receives its main supply of air from a branch from 
the principal right bronchus. 
The upper portion of the left lung consists of a single lobe (Z U), 
but with a short cleft on its anterior border, dividing it partially into 
a long, narrow, tongue-shaped, inferior portion, with the apex project- 
ing forwards and corresponding to the middle lobe of the right side 
* Tn the Pudu the number of rings of the trachea is almost exactly the same 
as in Moschus. I counted fifty above and ten below the upper right bronchus. 
