Diurnal Rapacious Birds. 135 



marked with the same letters as Fig. 4 of Plate IV. There are here 

 seen in addition, the bursa of Fabricius, s ; a section of the lung, I, 

 the position of the heart, u, that of the liver, h n, and of the ster- 

 num, v. 



The oesophagus, efg k, is 6 inches long, dilated anterior to the 

 thorax into a large sac, f, If in diameter, and 2 long. Its muscu- 

 lar coat is strong, its inner smooth. At its entrance into the thorax 

 at g, it contracts to \<±, and again enlarges to \\ in the proventri- 

 cular part, h. For an inch above the latter, the fibres are longitu- 

 dinal. The proventricular glands are close, cylindrical, with a nar- 

 row villous cavity, opening by a small orifice scarcely perceptible 

 in the middle of a small rounded eminence on the inner surface, 

 which presents the same appearance as in the eagle. 



Fig. 2 is a longitudinal section of the walls of the proventriculus. 

 Fig. 3 shows one of the glands enlarged ; a, the gland, b, the mucous 

 surface of the proventriculus, c, its muscular coat. Fig. 4 repre- 

 sents, at a three rows of the glands, at b the inner coat of the pro- 

 ventriculus, at c the fibres of the muscular coat reflected. Fig. 5 

 represents, much enlarged, the appearance of the inner surface of the 

 proventriculus. 



The stomach, Fig. 1. k, is 2<| long, 2^ broad, somewhat compres- 

 sed. Its fibres are disposed in fasciculi, and the tendinous centres 

 are -^ in diameter. The inner surface is smooth, glistening, and 

 minutely papillar. The pylorus, Fig. 6, has on the side next the 

 cardia three prominent rugae or valves, a, and opposite them on the 

 other side two small prominences. The intestine is 54 inches long. 

 The first fold, /, m, n, occupies the same position as in the eagle, 

 and the other parts may be described in the same manner. The 

 coeca, Fig. *J, c, c, are T 5 2 long, cylindrical, the rectum, a, 4| long, 

 much dilated. 



The inner surface of the upper part of the duodenum is like that 

 of the stomach. On its lower part and on the small intestine are 

 very long extremely delicate villi, which gradually become fewer. 

 The other parts are as in the eagle. 



In another male, the oesophagus was 7^ inches long, the stomach 

 3 ; the intestine 51 ; the coeca ^\ ; the rectum 4|. 



In a female, the oesophagus was 8 inches long, its sac 3 long and 

 2 in diameter, the proventricular part 1^ • the stomach 2 in dia- 

 meter, 1^ in thickness, its tendons T 8 5 ; the intestine 56, its diameter 

 below the pylorus only / g , but presently T 8 ^ its smallest diameter 

 2|-12ths ; the cceca T 8 5 long ; the rectum at first ^ in diameter, 

 half way down ^, in its dilated part 2 inches. 



