DR. J. MURIE ON THE ANATOMY OF THE WALRUS. 429 
larger lobes in the Walrus are more rounded in outline than in the other two genera, 
where they are rather triangularly figured and taper-pointed. 
The cystic lobe of Owen is deeply bifid, the right moiety more elongated than the 
left. Between them the pyriform gall-bladder is bound down by three separate folds 
of membrane, but it does not lie in a sunken fissure. The cystic duct is an inch long, 
and then receives an afferent from the left, and about a quarter of an inch below that 
another from the right. Two inches further on it partly penetrates the wall of the 
intestine, where, enlarging into a capacious duct, it continues for 5+ inches more, at last 
piercing the mucous coat, and opens into the intestine by a very minute orifice. 
The said enlargement of the ductus communis choledochus extends as a small cul-de- 
sac backwards from where it first penetrates the serous intestinal coat; and this portion 
of it is smooth-walled within; but further on, as it narrows, it becomes transversely 
trabecular. Though relatively capacious, this inflation of the intestinal portion of the 
bile-duct is not peculiar and alone met with in the Walrus, as stated by Home. 
The pancreas is large, broad, and flat, and with the usual glandular structure, of 
a yellowish or cream-colour ; the duct as mentioned. 
The mesenteric and abdominal lymphatic glands, as in the Pinnipedia generally, 
are numerous and of considerable dimensions; and within the folds of the mesentery 
exceedingly large lymphatic vessels are displayed. Indeed these lymphatic channels, 
convergent from the intestines towards the glands, are a remarkable feature, so distinct 
and large are they. Physiologically it may be inferred that assimilation is very rapidly 
effected in the Walrus, as doubtless is the case in the Seals, also fish-eaters, and equally 
remarkable for their voracity and speedy digestion. 
3. Urino-generative Apparatus.—The kidneys, as mentioned by Owen and Daubenton, 
are very compound, and composed of a vast series of lobules. In Phoca and Otaria the 
renal organs are similarly made up of adnate renules; but the three allied forms differ 
with respect to the relative size of these, and their being more or less adherent. In 
Otaria the lobules, especially externally, are more compactly set together, so that the 
surface presents only undulating manifestations of lobulation; the lobules also, although 
not individually counted, appear less numerous, and proportionally larger in size, than 
in the two other genera. richechus offers an intermediate character in these respects, 
the kidney of course being absolutely the largest. In Phoca, besides smaller renules 
and more defined marks of separation, there are also extensive wide venous ramifications 
or plexuses within the capsule, and unconnected with the cortical vascularity. 
Anterior to the renal arteries and to the inner margin of the kidneys the small supra- 
renal glands are found, as depicted in fig. 19, Pl. LY. 
The pents, ordinarily, is contracted within its abdominal sheath, but has no marked 
flexure or loop, as in Ruminants. The anterior boundary of the external opening or 
aperture (Pl. LIV. fig. 14, ap) of the sheath is situate some 5 inches behind the umbilicus 
302 
