248 
DBS. A. CAETE AND A. MACALISTEE ON THE 
this pouch, with the exception of one transverse fold of mucous membrane that traversed 
its fundus, was perfectly smooth. 
The fourth stomach in shape was broadly pyriform ; its length was about 144 inches, 
its circumference varying from 24 inches at its widest or proximal to 19 inches at its 
narrow or distal extremity ; its mucous surface was smooth, being destitute of rugae ; 
its coats were extremely thin, especially at its inferior margin, where they measured 
only one line in thickness ; superiorly the thickness increased to or 2 lines. Imme- 
diately below the opening from the third stomach, the fourth dilated and afterwards 
narrowed gradually towards its distal extremity; in this situation a few longitudinal 
rugae were irregularly distributed, and some glands were detected, more particularly 
round the orifice leading into the fifth stomach; this orifice presented a crescentic- 
shaped appearance on its proximal, but was oval in shape on its distal side, the difference 
in shape being caused by a semilunar fold or valve-like process which partially surrounded 
the aperture on the side corresponding to the fourth cavity ; this fold measured along 
the chord of its arc 1^- inch ; the distal side, or that corresponding to the orifice of the 
fifth stomach, was even narrower, measuring only 1 inch in diameter, and was surrounded 
with a few longitudinal rugae and the orifices of some mucous glands. 
The fifth or last stomach was small in comparison to the others ; in length it mea- 
sured only 94 inches, and in circumference about 20 inches ; its coats were slightly 
thicker than those of the fourth cavity ; its walls were studded with numerous glandular 
follicles, and it communicated with the duodenum through the medium of a small 
pylorus, which was guarded by a muscular sphincter and marked with numerous rugo- 
sities, both longitudinal and transverse ; the circumference of the pyloric orifice measured 
44 inches. This cavity seemed to be more especially the seat of gastric secretion, and 
so probably of digestion. In other Cetaceans the second or third stomachs are often 
supposed to be the true digestive cavities. 
On the outer or peritoneal surface and inferior border of these cavities the omentum 
was attached, not quite \ an inch in thickness, as in the case described by Hunter, but 
thicker at its left than at its right extremity ; however, nowhere did it exceed \ of an 
inch in thickness. The pneumogastric nerves ramified over the surface of all the 
stomachs, as also did the gastric arteries, but more especially on the coats of the second 
stomach ; the long descending branch of the gastric artery ran in a groove which sepa- 
rated the first from the second stomach. Immediately below the pyloric extremity of 
the fifth stomach the duodenum commenced and passed on to join the jejunum ; its 
entire course was superficial in the abdomen, only overlapped by the colon and omentum, 
and its length, measured to where it passed through the root of the mesentery, was about 
1 foot. The hepatic and pancreatic ducts lay on its posterior aspect ; these ducts joined 
each other about 4 an inch before they entered the outer or peritoneal covering of the 
intestine. The conjoined duct ran very obliquely for 2 inches between the coats of the 
intestine, opening in a valvular manner under a very peculiar hood-like fold of mucous 
membrane into the interior of the duodenum, at the distance of about 6f inches below 
the pyloric orifice. 
