THE CANADA GOOSE. 
197 
breadth at the anterior costal processes 3 inches ; the height of the crest 1 
inch 10 twelfths. The liver is small, the left lobe, which is 3 inches in 
length, covering but a very small portion of the stomach ; the right lobe 
is 5 inches in length ; the gall-bladder 2 inches 9 twelfths in length, 8 
twelfths in breadth, but contracted to 3 twelfths at the distance of 10 
twelfths from the extremity, where it enlarges to about 5 twelfths. The 
heart is 3 inches long, 2i inches in breadth at the base. 
The trachea measures 20J inches in length. At first it inclines a little to 
the left side, then on the anterior concave curve of the neck passes gradually 
to the right side, along which it proceeds as far as the lower part of the 
convex curve, when it separates in front from the neck, and forms a loop or 
abrupt curve, which is attached to the anterior part of the sternum, between 
the coracoid bones, thus approximating to the trachea of the Swans, but not 
entering the crest of the sternum. It then passes directly along the spine to 
behind the middle of the heart, where it bifurcates. In this respect also it 
is singular, in being more elongated than in the other species, of which the 
bifurcation is considerably anterior to the heart At the commencement its 
breadth is 6 twelfths ; presently after it enlarges to 8 twelfths, then contracts 
to 6 twelfths, and so continues until it begins to form the loop, on which its 
breadth is again 8 twelfths; after this it gradually tapers, so as to be only 2% 
twelfths wide at the inferior larynx, where its depth, however, is 5 twelfths. 
The form of that part is much the same as in the Swans, there being a similar 
elevated, bony, curved edge on each side, projecting beyond the commence- 
ment of the membrane of the bronchus, which is \ inch in length before the 
first ring appears. These membranes form a pretty large sac of a triangu- 
lar form ; and the continuation of the bronchus is extremely diminutive, 
with only 10 very small and slender cartilaginous half rings. The lateral 
muscles are large ; their anterior part gives off the sterno-tracheal at the 
distance of 2i inches from the inferior larynx ; but the posterior part, 
which is much larger, runs down 1 inch farther, and then terminates in a 
pointed form, not extending so far as to constitute an inferior laryngeal 
muscle. The rings of the trachea are broad, very firm, considerably flat- 
tened, 220 in number. 
