294 GREAT NORTHERN DIVER. 



layer composed of transverse or circular fibres, the internal of equally 

 distinct longitudinal fibres, which are not straight, but irregularly undulated. 

 The inner, or mucous coat, when contracted falls into longitudinal plaits. 

 The proventriculus is 2f inches long, the glandules large, roundish, simple, 

 and disposed in a continuous belt. Over this part, the transverse muscular 

 fibres are remarkably developed. The right lobe of the liver is 5f inches 

 long, the left lobe 5J. The heart is very large, of a broadly conical form, 3 

 inches long, 2f inches in breadth. The stomach is three inches long, 2\ in 

 breadth, of an elliptical form, a little compressed; its lateral muscles 9 lines 

 in thickness, and composed of strong large fasciculi; the tendons \\ inches in 

 diameter; the cuticular lining thick, its upper and lower parts marked with 

 strong longitudinal ridges having numerous transverse fissures; the grinding 

 surfaces irregularly wrinkled, with a deep fissure down the middle of each. 

 The pylorus is 8 lines in diameter when distended, and is destitute of valve, 

 but has a strong prominent rim. In the stomach were remains of fishes, and 

 some pebbles, chiefly quartz, the largest 4 lines long. The intestine 

 measures 6 feet 6 inches in length, and varies in diameter from 8 to 6 lines. 

 The rectum is 3^ inches long, the cloaca extremely large, forming a cavity 

 about 3 inches in diameter. The cceca are If inches long, cylindrical, 

 rounded at the extremity; one of them 7 lines, the other 9 lines, in diameter. 

 The trachea, when moderately extended, measures 13|- inches in length, 

 inconsiderably depressed, its transverse diameter at the upper part 9^ lines, 

 at the lower 6-| lines; the rings cartilaginous, of moderate breadth, uniform, 

 with a contraction in the middle before and behind, their number 134, the 

 four lowest united. The bronchi are composed of about 20 narrow car- 

 tilaginous half rings. The contractor muscles are very broad, but thin, their 

 fibres irregularly disposed in front; they become thicker and narrower 

 toward the lower part, and are continued beyond the sterno-tracheal muscles, 

 which come off from the 20th ring from the inferior larynx, to the mem- 

 brane between the last tracheal and first bronchial ring. 



