COMMON STORM-PETREL. 461 



than the head, slender, much compressed, decurved at the 

 end, and acute. The upper mandible with its dorsal line 

 concave and ascending to the nostrils, then suddenly deflected, 

 afterwards for a short space straight, finally arcuate and 

 much decurved, the ridge carinate, with its sides sloping, 

 rising into a tube for the nostrils, beyond which it is nar- 

 rowed, the sides convex, and separated from the ridge by a 

 groove ending before the point, the edges thin, approximating 

 toward the end so as to form a deep groove, the unguis nar- 

 row, decurved, and pointed ; the lower mandible with the 

 intercrural space narrow and pointed, the sides erect at the 

 base, inclinate toward the end, their lower outline slightly 

 decurved, ending in a slight prominence, beyond which the 

 dorsal line is declinate and slightly concave, the edges approxi- 

 mating so as to come in contact near the tip ; the gape-line 

 sinuous. 



The mouth is of moderate width, the palate convex, with 

 two lateral ridges, the upper mandible with a medial promi- 

 nent line. The tongvie, five-twelfths and a half in length, is 

 much flattened, at the base emarginate and serrulate, horny 

 and tapering at the point. The oesophagus, an inch and six- 

 twelfths long, has a nearly uniform width of two-twelfths and 

 a half, and opposite the heart expands into an enormous sac, 

 which gradually enlarges to the width of seven-twelfths, 

 forming a broad rounded fundus, then curves forwards on the 

 right side, and terminates in a very small gizzard. This 

 enlarged part, over which the gastric glandules are dispersed 

 at considerable intervals, is the proventriculus ; its length to 

 the fundus is an inch and a twelfth, but along its greater 

 curve nearly two inches. The stomach is very small, a 

 quarter of an inch in length, and nearly of the same breadth, 

 elliptical, with rather strong muscles, roundish tendons, and 

 rugous epithelium. It is resupinate, or reversed in its posi- 

 tion, so that the duodenum comes ofi" from the left side, and 

 in order to gain its usual situation curves upwards and to the 

 right, behind, and in contact with the upper surfaces of the 

 lower, then forms the usual duodenal fold, on receiving the 

 biliary duct curves backward beneath the kidneys, and forms 

 several convolutions, which terminate above the proventri- 



