PEREGRINE FALCON. 367 



Female. Length to end of tail 19i inches, to end of wings 18, to 

 end of claws 20 ; extent of wings 42. 



An adult male, sent from Boston by Dr T. M. Brewer. The 

 roof of the mouth flat, with two longitudinal papillate ridges ; the up- 

 per mandible with a broad median ridge. The aperture of the mouth 

 1 inch 1^ twelfth across ; the tongue 9 twelfths long, fleshy, sagittate 

 and papillate at the base, concave above, grooved on the back beneath, 

 the point horny, rounded, and slightly emarginate. The cesophagus 

 is 6 inches long, 1 inch in width at its upper part, immediately dilating 

 into a large crop, of which the greatest width is 1 inch 9 twelfths ; 

 on entering the thorax it contracts to 8 twelfths ; the proventriculus 

 is 10 twelfths in breadth. The stomach is round, 1 inch 11 twelfths in 

 diameter, a little compressed ; its muscular coat very thin, and composed 

 of a single series of large fasciculi ; the tendons roundish, and ^ inch 

 in diameter. The duodenum curves in the usual manner, returning at 

 the distance of 5^ inches. The intestine is 3 feet long, rather slender, 

 the width of the duodenum being 4^ twelfths, of the rest diminishing 

 to 2 twelfths. The coeca are merely two slight sacs, 1^ twelfth long. 

 The cloaca is very large, globular, 1;^ inch in diameter. The proven- 

 tricular glands are exceedingly small, cylindrical, 1 twelfth long, and 

 forming a belt 10 twelfths in breadth. The inner surface of the sto- 

 mach is smooth, and the pylorus has a kind of valve composed of three 

 small knobs. 



The heart measures 1 inch 9 twelfths in length, 1 inch 2 twelfths 

 in breadth. The lobes of the liver are about equal. 



The trachea is 4^ inches long, rather wide, considerably flattened ; 

 its breadth at the upper part 5 twelfths, at the lower 3^ twelfths. The 

 rings, 72 in number, are very firm ; the lateral muscles very large, as 

 are the sterno-tracheales, which are continuous with the anterior part 

 of the lateral muscles, while a strong slip passes on each side from their 

 posterior part to be inserted upon the membrane interposed between 

 the last ring of the trachea and the first of the bronchus. The last 

 entire ring of the trachea is divided by a transverse bony ridge, as in 

 all American birds of this family excepting the Caracara. The bron- 

 chi are rather short and wide, one of 15, the other of 17 cartilaginous 

 half rings. 



Adult Female. The mouth measures 1;^ inch across. The ceso- 



