are = ee 
THE VISCERAL ANATOMY OF THE GROUND-RAT. 227 
ally diminishing a foot from the ileo-cwcal valve and ceasing altogether 
4 inches further on, the ridges continuing as simple folds like railway 
lines. 
Commencing colon of Aulacodus swindernianus, slit open on the non-attached 
border, showing the ileo-cecal valve on the left, beyond which is the commencing 
cecum ; the intestine, with the two longitudinal ridges, running to the right ; 
a, terminal portion of small intestine. 
The liver possesses a gall-bladder which is short and pyriform. It 
presents all the typical fissures and lobes. The median fissure is 
slightly bridged over with hepatic tissue on the abdominal surface 
behind. The right and left lateral fissures very nearly separate off 
the lateral lobes as distinct glands; the caudate lobe is also only 
slightly attached. The left lateral lobe is the largest, next the right 
central, in which the cystic fossa and fissure are both deep. The 
right lateral is the smallest of the four main lobes; the caudate is 
smaller than any of them; and the Spigelian is only a flat flake of 
hepatic tissue. 
The right Jung possesses four lobes, of which the lowest is the 
largest, and the top one as small as the fourth, azygos one. An acces- 
sory bronchus joins the right bronchus. The left lung has two lobes, 
the upper the smaller, having two upper diverticula; there is no left 
accessory bronchus. 
The aorta primarily branches into two trunks for the upper extre- 
mities, an innominate and a left subclavian; the left carotid soon 
leaves the innominate. 
Q 2 
