NORMAL ANATOMY OF THE LIVER. 
omentum, and which accompanies them along 
the portal canals and interlobular fissures to 
their ultimate distribution in the substance of 
the lobules. It forms for each of the lobules a 
_ distinct capsule. which invests it on all sides 
_with the exception of its base, and is then ex- 
panded over the whole of the exterior of the 
» constituting the proper capsule of the 
liver. Glisson’s capsule serves to maintain the 
_ portal vein, hepatic artery, and hepatic ducts in 
‘connection with each other, and attaches them 
_also to the surface of the portal canals; it con- 
hects the trunks of the hepatic veins to the 
_ Surface of the canals in which they run ; it sup- 
j the lobules and binds them together, and 
its exterior expansion it invests and protects 
entire organ. But Glisson’s capsule, ob- 
es Kiernan, “ is not mere cellular tissue ; 
“it is to the liver what the pia mater is to the 
brain; it is a cellulo-vascular membrane, in 
which the vessels divide and subdivide to an 
"extreme degree of minuteness ; which lines the 
portal canals, forming sheaths for the larger ves- 
Sels contained in them, anda web in which the 
smaller vessels ramify; which enters the inter- 
Tobular fissures, and with the vessels forms the 
apsules of the lobules, and which finally enters 
@ lobules, and with the bloodvessels expands 
itself over the secreting biliary ducts. Hence 
arises a natural division of the capsule into three 
portions, a vaginal, an interlobular, and a lobu- 
rtion.”’ 
e vaginal portion of the capsule is loose 
d abundant; it occupies the portal canals 
and incloses the portal vein, hepatic duct, and 
epatic artery. In the larger canals (fig. 36, 
8,) it completely surrounds these vessels, but 
in the smaller ones (fig. 37,) is situated only 
On that side of the portal vein upon which 
he duct and artery are placed, the opposite side 
Of the vein being in contact with the capsular 
Surfaces of the lobules. It constitutes a me- 
dium for the ramification of the vaginal plexus 
rmed by the vein, artery, and duct, previously 
their entrance into the cellular interval of the 
terlobular fissures. 
_ The interlobular portion forms the cellular 
capsule for each of the lobules and the bond of 
ion between their contiguous surfaces. It 
pports the plexiform ramifications of the por- 
al vein, hepatic artery, and duct, and is the 
medium of vascular communication between 
all the lobules of the liver. 
_ The lobular portion forms sheaths for the 
Minute vessels which enter the lobules, and a 
oie parenchyma for the substance of those 
ies. 
_ The portal vein is formed by the union of the 
ie trunks which return the blood from the 
ylopoietic viscera, viz., the superior and in- 
ior mesenteric, the splenic, and gastric veins. 
Bp mencing behind the pancreas where all 
ese veins converge, the portal trunk ascends 
along the right border of the lesser omentum, 
lying behind the hepatic artery and ductus com- 
munis choledochus to the transverse fissure. 
At the transverse fissure it bifurcates into two 
tunks which enter the right and left lobes, 
and divide and subdivide as they take their 
167 
course through the portal canals, until they are 
ultimately lost in the substance of the lobules. 
The branches of the portal vein are accompanied 
throughout their course by branches of the hepatic 
duct and hepatic artery, and they are inclosed 
and connected to the capsular surfaces of the 
lobules forming the portal canals, by Glisson’s 
capsule. The branches of the portal vein are 
divisible into vaginal, interlobular, and lobular. 
The vaginal branches (fig 36, 3, fig. 38, f') 
are the small veins which ase-given off by the 
portal trunks during their passage through the 
portal canals, and which are intended to convey 
AN y "S\ 
“> 
~ 
‘ 
e) 
A transverse section of a large portal canal and its 
vessels. The lobules are in a state of general con- 
gestion, their central portions being more congested 
than their marginal portions. — From Kiernan’s 
japer. 
No. 1, Superficial lobules forming the parietes of 
the canal. In some the intra-lobular vein does not 
extend to the surface of the canal; this appearance 
depends upon the direction in which the incision is 
made. 2, The portal vein. 3, Vaginal branches 
arising from the vein and dividing into interlobular 
branches which enter the interlobular spaces. 
4, Hepatic duct. It is seen to give off vaginal 
branches which divide into interlobular ducts, the 
latter enter the interlobular spaces. 5, The hepatic 
artery ; itis seen giving off vaginal branches which 
divide into interlobular branches, and the latter 
enter the spaces with the branches of the portal 
vein and hepatic duct, 6, Three interlobular ves- 
sels, a duct, vein, and artery, entering each inter- 
lobular space. 7, A part of the vaginal plexus. 
8,8, Glisson’s capsule, which completely surrounds 
the vessels. 
their blood into the substance of the lobules. 
In the cellular sheath of Glisson’s capsule which 
surrounds the portal vein, they inosculate freely 
with each other and form, together with the va- 
ginal branches of the duct and artery, a vascu- 
lar plexus, named from its situation the vaginal 
plexus. This vaginal plexus establishes a com- 
munication between the vaginal veins through- 
out the portal canals, and serves to equalise the 
supply of blood to the lobules. Opposite each 
interlobular space an interlobular vein is given 
off, which enters between the lobules and rami- 
fies in the interlobular fissures. In the larger 
portal canals (fig. 36,) the vaginal plexus com- 
pletely surrounds the portal vein, hepatic duct 
