ON THE ANATOMY OF THE NORTHERN BELUGA. 405 
the third. On the supposition, therefore, that a process of rumination takes 
place in the cetacea, we are compelled to assume that the food is regurgitated 
from either the first or second compartment, to be afterwards carried back into 
the same,—a process which, if it ever takes place, is essentially different to 
that which occurs in the true ruminants. Secondly, The strictly animal diet 
of the toothed whales may further be advanced as an argument against this 
view, the nature of the food precluding the necessity of a process which, so 
far as positive knowledge goes, is strictly confined to truly herbivorous mam- 
malia. Thirdly, The form and arrangement of the teeth in the zoophagous 
cetacea is such as seems but ill-adapted for carrying out their part in 
the supposed function of rumination. As M. Fiscuer® has well said, when 
discussing this hypothesis :—“ Bon nombre de cétacés (Balein, Ziphius, Gram- 
pus) sont complétement dépourvus de dents ou n’en possedent qua l’extrémité 
du rostre.” 
Intestine.—The gut from pylorus to anus measures 54 feet inlength. At its 
commencement it is wider than elsewhere, its diameter here being double that 
of any other part of the intestine. This dilated portion measures 5 inches in 
length, and receives the previously united hepatic and pancreatic ducts which 
open into it 4 inches from the pylorus, after lying in the wall of the gut for a 
distance of 2 inches. Immediately beyond the duodenal dilatation the gut, 
when flattened, measures 24 inches in breadth, whilst at its rectal extremity 
this measurement diminishes to 14 inch. The intestinal tube, therefore, de- 
creases from its commencement to its termination, but the calibre of its lower 
half is somewhat irregular in consequence of constrictions which occur every 
here and there. There is no trace of any subdivision of the gut into 
small and large intestines, and the czecum is entirely absent. The intestine is 
attached to the superior abdominal wall by a mesentery measuring 9 inches in 
breadth. 
The mucous membrane lining the duodenal dilatation is uniformly smooth 
and destitute of valvulz conniventes. One inch beyond the point of entrance 
of the combined hepatic and pancreatic ducts, however, the valvule begin to 
appear. At first small and faintly marked, they rapidly become valvule and 
form circular valve-like projections, measuring 2 of an inch in depth, attached 
to the entire circumference of the gut. These large folds alternate with others 
of smaller size, which do not extend round the entire gut. The larger valvule 
are found along the upper half of the intestine, but below this they become 
smaller, and are less regularly disposed. In the lower 9 feet of the gut they are 
scarcely recognisable. The mucous membrane beyond the duodenum possesses 
a delicate, soft, and velvety appearance. Beyond the pyloric valve the surface 
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