NORMAL ANATOMY OF THE LIVER. 
from the preceding in being lodged in canals 
_ formed by the capsular surface of the lobules, 
the hepatic venous canals, which are analogous 
_to the portal canals excepting in the absence 
_ of a proper investment of Glisson’s capsule. 
It follows from this circumstance, that there 
are no vessels in connection with the hepatic 
veins at all resembling the vaginal branches 
_ and plexuses of the portal vein. The general 
course of the hepatic veins is from the two 
_ surfaces and free margin of the liver towards 
_ the vena cava in the posterior border; that of 
_ the portal vein radiates from the transverse fis- 
sure in the centre of the under surface to all 
_ parts of the circumference; hence the two 
veins cross each other in their course, the 
_ former proceeding from before backwards, and 
the latter from the centre towards the circum- 
ference. In examining either of these sets of 
vessels, we should, therefore, be guided in the 
direction of our section by this peculiar ar- 
“rangement. There is another mode by which 
_we arrive at a knowledge of the means of dis- 
_criminating between the two veins in a section. 
The hepatic vein being closely adherent to the 
lobules forming the canal in which it is lodged, 
“remains open, and retains the form of its cy- 
linder upon the face of a section ; it may also 
be recognised by being solitary. The portal 
yein, on the contrary, being surrounded by the 
loose, vasculo-cellular web of Glisson’s cap- 
Sule, is permitted to collapse; it is also charac- 
terised by being associated with a branch of the 
hepatic artery and duct. In the consideration 
of the hepatic veins | shall describe, first, the 
‘intralobular, next the sublobular, and then the 
hepatic trunks. 
_ In the centre of each lobule is situated an 
intralobular vein (fig. 34, 5,) which is 
formed by the convergence of from “ four to 
‘six or eight” minute venules, from the processes 
‘upon the surface of the lobule. In the super- 
ficial lobules, the intralobular vein commences 
directly from the surface, and the minute ve- 
mules by which itis formed may be seen in an 
freee injection converging from the circum- 
nce towards the centre. The vein then 
akes its course through the centre of the longi- 
tudinal axis of the lobule, and piercing the 
middle of its base opens into the sublobular 
vein. The intralobular veins have no direct 
communication with the portal vein or with 
the hepatic artery, and they simply serve to 
‘collect the blood which has circulated through 
the lobular venous plexus, and convey it into 
the general current of the hepatic veins. 
The sublobular veins (fig. 34) are named from 
their position at the base of the lobules. They 
are lodged in canals which are formed by the 
bases of all the lobules of the liver. They are 
extremely thin and “delicate in texture,” and 
lie in close contact with the substance of the 
lobules, so that upon laying open one of these 
veins, the bases of the lobules may be seen 
distinctly through its coats. In the centre of 
the base of each of the lobules will be ob- 
served the opening of the intralobular vein, so 
that the whole internal surface of the vein is 
Pierced by these minute openings. In the 
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smaller portal veins, on the other hand, where a 
number of small foramina were seen upon the’ 
internal surface of that side of the vessel 
which lay in contact with the canal, and where 
the outline of the lobules was also perceptible, 
it was observed that the small openings cor- 
responded with the interlobular spaces, and were 
the entrances of the interlobular veins. 
The hepatic trunks receiving the blood from 
the sublobular veins take their course along the 
“hepatic venous canals,” andterminate by 
two large openings corresponding with the 
right and left lobes in the inferior cava, at the 
oint where that vessel is lying deeply im- 
dded in the posterior border of the liver. A 
number of minor hepatic veins also terminate 
in the cava at this part of its course. The he- 
patic venous canals resemble the portal canals 
in being formed by the capsular surfaces of the 
lobules, lined by a prolongation of the proper 
capsule. The hepatic trunks are thick and 
dense in their structure, and their external coat 
is composed of “longitudinal bands,” From 
the thickness of their texture the outline of the 
lobules is not apparent through their coats, nor 
have they any intralobular veins opening into 
them. 
The coats of the hepatic veins are supplied 
with blood by the hepatic artery, and the venous 
blood is returned to the ramifications of the 
portal vein. 
The lymphatic vessels of the liver are divi- 
sible into the deep and superficial. The former 
take their course through the portal canals, and 
through the right border of the lesser omentum, 
to the lymphatic glands situate in the course 
of the hepatic artery, and along the lesser curve 
of the stomach. They are easily injected (by 
rupture of course) from the hepatic ducts, and 
Kiernan remarks, that “ injection sometimes 
passes from the arteries and portal veins into 
the lymphatics. I have frequently seen them 
in the right border of the lesser omentum, 
when distended with injection, as large as small 
veins. The superficial lymphatics, (figs. 32 and 
33,) are situated in the cellular structure of the 
proper capsule, over the whole surface of the 
liver. Those of the convex surface are divided 
into two sets; 1st, those which pass from be- 
fore backwards ; and 2d, those which advance 
from behind forwards. The former unite to 
form trunks, which enter between the folds of 
the lateral ligaments at the right and left extre- 
mities of the organ, and of the coronary liga- 
ment in the middle. Some of them pierce the 
diaphragm, and join the posterior mediastinal 
glands; others converge to the lymphatic 
glands situated around the inferior cava. Those 
which pass from behind forwards consist of two 
groupe: one ascends between the folds of the 
broad ligament, and perforates the diaphragm 
to terminate in the anterior mediastinal glands ; 
the other Curves around the anterior margin of 
the liver to its concave surface, and from thence 
to the glands in the right border of the lesser 
omentum. The lymphatic vessels of the con- 
cave surface are variously distributed according 
to their position ; those from the right lobe 
terminate in the lumbar glands ;—those from 
