MARSUPIALIA. 
The stomach of the Kangaroo may be re- 
garded as consisting of a left, a middle, and a 
right or pyloric division. The left extremity of 
the stomach is bifid, and terminates in two 
round cul-de-sacs. The sacculi of the stomach 
are produced, like those of the colon, by three 
narrow longitudinal bands of muscular fibres, 
which gradually disappear, together with the 
sacculi at the pyloric division. One of the 
longitudinal bands runs along the greater cur- 
vature, at the line of attachment of the gastro- 
eolic omentum ; the others commence at the 
base of the left terminal pouches, and run, one 
along the anterior, the other along the posterior 
side of the stomach: the interspace, between 
these bands, forming the lesser curvature of 
the stomach, is not sacculated. The largest of 
the two terminal sacculi (d, fig. 124) is lined 
with an insulated patch of vascular mucous 
membrane, which is continued for the extent 
of five inches into the cardiac cavity; the epi- 
thelium is continued from the csophagus in 
one direction into the nearest and smallest sac- 
culus, and extends in a sharp-pointed form for 
a considerable distance in the opposite direction 
into a series of sacculi in the middle compart- 
ment of the stomach (c): this epithelium is quite 
smooth. The vascular mucous surface recom- 
mences by a point at the great curvature, near 
the beginning of the middle compartment, and 
gradually expands until it forms the lining of 
the whole inner surface of the right half of the 
stomach. Three rows of clusters of mucous fol- 
licles (g, g) are developed in the mucous mein- 
brane of the pyloric half of the middle com- 
partment; they are placed parallel with the lon- 
gitudinal muscular bands: about fifteen patches 
are situated along the greater curvature, and there 
are nine in each of the anterior and posterior 
rows. These glandular patches disappear alto- 
gether inthe pyloriccompartment of thestomach, 
where the lining membrane is thickened, and 
finely corrugated; but immediately beyond the 
pylorus there is a circular mucous gland three- 
fourths of an inch broad: the non-sacculated 
pyloric division of the stomach was five inches 
in length. 
In the smaller species of Kangaroo the 
stomach is less complicated than in the Macro- 
pus major ; the number of sacculi is fewer: in 
Macropus Parryi, Ben. the third longitudinal 
band at the great curvature of the stomach is 
almost obsolete: in the Brush-tailed or Rock 
Kangaroo, ( Macropus penicillatus, ) the cardiac 
extremity terminates in a single sub-clavate cul- 
_ de-sac. In all the species which I have exa- 
mined the esophagus terminates in the middle 
division of the stomach, close to the produced 
crescentic fold which separates it from the cardiac 
compartment. In the great Kangaroo a second 
slighter fold is continued from the right side of 
the cardiac orifice parailel with the preceding, 
and forming with it acanal, somewhat analogous 
to that in the true ruminating stomachs, and 
along which fluids, or solid food not requiring 
previous preparation in the cardiac cavity, might 
be conducted into the middle compartment. 
I have more than once observed the act of- 
rumination in the Kangaroos kept in the Viva- 
301 
rium of the Zoological Society. It does not 
take place while they are recumbent, but when 
the animal is erect upon the tripod of the hind 
legs and tail. The abdominal muscles are in 
violent action for a few seconds, the head is 
then a little depressed, and the cud is masti- 
cated by arapid rotatory motion of the jaws. This 
act is by no means repeated in the Kangaroos 
with the same frequency or regularity as in the 
true Ruminants. A fact may, however, be 
noticed as an additional analogy between them ; 
balls of hair, cemented by mucus, adpressed 
and arranged in the same direction, are occa- 
sionally formed in the stomach, of which I 
have met with two, of an oval shape, in the 
Macropus Parryi. 
In the genus Hypsiprymnus the stomach is 
as singularly complicated as in the Kangaroos, 
and the complication is essentially the same in 
both; arising from the sacculation of the pa- 
rietes of a very long canal by a partial dispo- 
sition of shorter bands of longitudinal fibres ; 
but in the Potoroos this sacculation is confined 
to that part of the stomach which lies to the 
left of the esophagus, while the right division 
of the cavity has the ordinary form and struc- 
ture of the pyloric moiety of a simple stomach. 
The left or cardiac division is enormously de- 
veloped ; in relative proportion, indeed, it is 
surpassed only by the true ruminant stomachs, 
in which both the rumen and reticulum are 
expansions of the corresponding or cardiac 
moiety of the stomach. The relation of the 
stomach of a Potoroo to that of a Kangaroo 
may be concisely expressed by stating that the 
termination of the cesophagus in the former is 
removed from the commencement of the middle 
sacculated compartment to its termination. 
When fluid is injected into the stomach of 
a dead Potoroo, it distends first the pyloric 
division; it is probably by a kind of anti- 
eristaltic action that the aliment is propelled 
into the long sacculated cecum to the left of 
the cesophagus. 
The moditications of the epiploon, as an ap- 
pendage to the stomach, may here be noticed. 
n the Kangaroo it is of very moderate size, 
being continued loosely from the stomach to 
the transverse colon, but not extended beyond 
that part. The posterior layer lies between the 
stomach and the intestines, and affords a good 
illustration of one of the uses of the epiploon, 
as it evidently prevents these parts from inter- 
fering with each other’s motions. The anterior 
layer generally contains more or less fat. In 
the Petaurus the great omentum is continued 
from the great curvature of the stomach, and 
the commencement of the duodenum. In the 
Phalangers it is of considerable extent, and 
is usually loaded with fat. In the Opossums I 
have found it generally devoid of fat, when 
this substance has been accumulated in other 
parts. In the Phascogales and Dasyures the 
epiploon is of moderate size, and contains 
little or no fat. 
Having seen that, with the exception of the 
Potoroos and Kangaroos, the stomach is simple 
in the Marsupialia, presenting only some addi- 
tional mucous glands in the Koala and Wom- 
