. The birds of America : from drawings made in the United States and their territories . s, to whichthe Grebes might be supposed to be allied, on account of the structure oftheir feet. On the other hand, they differ from the Divers and Cormorantsin the form of the oesophagus, which in these birds is extremely wide,whereas in the Grebes it is exceedingly contracted, and more resembles thatof the Coots, Gallinules, and Rails. The proventriculus is intermediatebetween that of the birds just mentioned and the Cormorants. There is apyloric sac of small size, approximating to that of the Pelican fam
. The birds of America : from drawings made in the United States and their territories . s, to whichthe Grebes might be supposed to be allied, on account of the structure oftheir feet. On the other hand, they differ from the Divers and Cormorantsin the form of the oesophagus, which in these birds is extremely wide,whereas in the Grebes it is exceedingly contracted, and more resembles thatof the Coots, Gallinules, and Rails. The proventriculus is intermediatebetween that of the birds just mentioned and the Cormorants. There is apyloric sac of small size, approximating to that of the Pelican family. Thestomach is moderately distended with a great quantity of feathers, apparentlythose of the bird itself, or of some species of the same genus. These feathersare intermixed with vertebrae of small fishes, easily distinguishable by theirconcave surfaces and three prominent spines. The duodenum curves roundthe stomach, returning at the distance of 5J inches, ascending to the liver asusual, passing down the right side, and forming several convolutions, the THE RED-NECKED GREBE. 315. 316 THE HORNED GREBE. number of turns being twelve. Its length is 33 inches; its width |- inch atthe upper part, towards the rectum only 3 twelfths. The coeca are 2 incheslong, 2 twelfths in breadth, uniform, unless at the base, where they arenarrower; their distance from the extremity 3 inches. The cloaca isglobular, 1^ inches in diameter. The trachea is 94 inches long, of the nearly uniform width of 3i twelfths,unless at the lower part, when it is narrowed to 2 twelfths; flattened in itsupper half, and compressed in the lower; the rings moderately firm, 180 innumber. The Grebes differ from almost all other birds in having thebronchial rings complete and firmly ossified. In the present species, theyare only 8 in number, the remaining part of the bronchi being are the usual cleido-tracheal muscles; the sterno-tracheal, part ofwhich is continuous with the lateral muscles, but the i
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Keywords: ., bookcentury1800, bookdecade1840, booksubjectbirds, bookyear1840
