378 BROAD-WINGED HAWK. 



the greatest width is 1 inch 10 twelfths ; the proven triculus 11 twelfths, 

 its glands very small, cylindrical, occupying a belt 1 inch in breadth. 

 The stomach is large, round, a little compressed, 1| inch in diameter ; 

 its muscular coat very thin, and composed of a single series of fasciculi ; 

 its inner surface smooth, soft, somewhat rugous ; the tendons 8 twelfths 

 in diameter. The pylorus has three prominent triangular valves, and 

 a small prominence exterior to the margin. The duodenum curves in 

 the usual manner, folding back at the distance of three inches. The 

 intestine is 39 inches long ; its greatest width 2^ twelfths, the smallest 

 towards the rectum nearly 2 twelfths. The rectum is 3^ inches long, 

 including the cloaca, its breadth at the commencement 4 twelfths, 

 gradually enlarging to 6 twelfths ; the cloaca globular, If inch in dia- 

 meter. The cceca unequal, one 3 twelfths long, the other IJ twelfth. 

 The trachea is 4/^ inches long, flattened, 4 twelfths broad at its 

 upper part, 2 twelfths at the lower ; the rings 95, very thin and partially 

 ossified. The bronchi of 21 rings each. The contractor muscles are 

 very strong, directly continued into the sterno-tracheal, and sending a 

 small slip on each side to the last ring. 



RED-TAILED HAWK. 



Falco borealis, Gmel. 



PLATE LI. Vol. I. p. 265. 



It is to be regretted that authors have so often imposed upon birds 

 names which are not strictly applicable to them. In the present case 

 the specific name " borealis" is far from correct, for this species is very 

 abundant during the whole year in our Southern and Western Districts, 

 indeed in the proportion probably of five for one found in the northern. 

 This, it would appear, was not known to Wilson ; and, although a 

 good number breed in the Middle Districts, and some remain there in 

 winter, those which have been obtained farther north I look upon as 

 stragglers. Some of these have been shot at York Factory, on the 

 plains of the Saskatchewan, on the Rocky Mountains, and on the Co- 

 lumbia River. I have found this species abundant in the Texas, where 



