30 ESSAY ON THE DESCRIPTIVE ANATOMY OF THE 
and surrounded by cellular tissue, which sheaths grooves or 
canals cut in various directions in the substance of the organ. 
These are the portal canals, and the cellular tissue in question 
is Glisson’s capsule. 
The vessels and ducts ramifying on the sheath acquire the 
name of vaginal branches, and as they are traced between the 
lobules they are termed interlobular. Here the unassisted eye 
ceases to take cognizance of their further relation, but with 
careful dissection and a common pocket lens they may be 
traced to the lobules, which they enter; and the blood of the 
hepatic artery and portal vein is emptied into a common set of 
vessels, the hepatic vein. The relation of these vessels in the 
lobules may be seen on the surface in a good injected specimen 
of liver, where the hepatic veins have been injected one colour, 
and the other vessels differently. By this means the centre of 
the lobule is coloured with the injection thrown into the hepatic 
veins, and the circumference with that of the portal vein. 
The hepatic veins issuing from the lobules cross the structure 
of the liver in separate grooves, formed by the coalescence of 
the hepatic particles, so that their base is in contact with the 
veins, and hence the name of the latter is that of the sub-lobular 
hepatic veins. These empty into the posterior cava by several 
orifices, as well as by two larger ones, guarded by semi-lunar 
valves, situated just at the foramen dextrum of the diaphragm. 
In addition to the bloodvessels and ducts of the liver, it is 
supplied with nerves from the solar plexus, which ramify with 
the vessels. 
The lymphatics of the liver are abundant, and arranged, like 
in other organs, as a superficial and deep set, which inosculate 
freely in the substance of the organ, and, uniting to form several 
branches, they issue from the porta of the liver, passing through 
some lymphatic glands situated round the fissure, and from this 
they advance to the receptaculum chyli. 
Pancreas. 
The pancreas is a compound vesicular or racemose gland, 
being much of the same nature as the salivary glands. 
The pancreas occupies the interval between the layers of the 
transverse mesocolon, along the upper surface of the transverse 
colon. 
Its attachments are merely cellular, with the exception of 
the pancreatic duct, which attaches it pretty closely to the 
duodenum. 
The pancreas is spoken of as having a body, a head, and a 
tail. The body of the pancreas is that part stretched across the 
