BEWICK'S SWAN. 671 



in part of the duodenum, gradually contracting to five-twelfths. 

 The coeca come off at the distance of seven inches from the 

 extremity, and are ten inches in length, at the commence- 

 ment two-twelfths and a half in width, their greadest breadth 

 eight-twelfths, narrowed to four-twelfths. 



The trachea at first eight-twelfths in breadth, contracts to 

 five-twelfths, then enlarges to seven-twelfths ; it is consider- 

 ably flattened until near the furcula, when it becomes cylin- 

 drical, enters a cavity formed in the crest of the sternum, and 

 is continued into a vacant space beyond it, and extending to 

 within half an inch of the posterior extremity of the bone, in 

 which it forms a horizontal loop, returns, becomes vertical, 

 and curving in the furcula enters the thorax to the length of 

 three inches. The inferior larynx, composed of several united 

 rings, is laterally compressed, measuring at the end in height 

 an inch, and in breadth six-twelfths. Appended to the last 

 or semi-lunar ring on each side is a narrow membrane, to 

 which is attached an extremely slender half-ring. Within 

 this small membrane is a larger extending to the first bron- 

 chial ring. The bronchi, composed of about twenty thin 

 bony rings, some of which are united by processes, are two 

 inches in length, enlarged beyond the middle into a some- 

 what globular sac, half an inch in breadth, and ultimately 

 contracted to four-twelfths. 



The nostrils are oblongo- elliptical, five-twelfths and a 

 half in length, direct, medial. The aperture of the eyes four- 

 twelfths and a half. The legs are short, very stout ; the tibia 

 bare for an inch and a quarter ; the tarsus considerably com- 

 pressed, reticulated ; the hind toe very diminutive, the outer 

 reticulated to the third joint, the middle toe nearly as far as 

 the second joint, the inner to that joint, their scutella respec- 

 tively thirty-five, thirty-three, and twenty ; the membranes 

 full. The claws of moderate size, strong, arched, compressed, 

 rather acute, that of the middle toe with its inner edge 

 dilated, and the tip rounded. 



A portion of the forehead, and the space from the bill to 

 the eyes, and margining them, bare. The plumage as in the 

 other species ; the wings very long, with thirty-three quills, 

 the second and third equal and longest, the outer three deeply 



