Photograph of specimen hardened _in situ_.
]
The liver is relatively large, its average weight being about 4 to 4½
pounds (ca. 2 kg.). It is thick and very strongly curved.[114] It is
divided by three deep interlobar incisures into four principal
=lobes=—=right lateral=, =right central=, =left central=, =left
lateral=; the last of these is usually considerably the largest. On the
upper part of the right lateral lobe is the =caudate lobe= and its
process. That part of the right central lobe which lies below the portal
fissure and to the left of the gall-bladder and cystic duct is
homologous with the quadrate lobe of man. The parietal surface is
extremely convex, its most anterior part reaching to a plane through the
lower part of the sixth or seventh intercostal space. The visceral
surface is deeply concave; most of it is related to the stomach, for
which there is a correspondingly large and deep gastric impression.
There is a duodenal impression on the upper part of the right lateral
lobe, but no renal impression, as the right kidney does not touch the
liver. The fossa for the gall-bladder is mainly on the right central
lobe, but also in part on the adjacent surface of the left central lobe.
The posterior vena cava enters the dorsal border of the caudate lobe and
soon becomes entirely embedded in the gland substance, emerging only at
its passage through the diaphragm. The œsophageal notch is large and is
occupied mainly by the large right crus of the diaphragm. The right
lateral border extends backward to the upper part of the twelfth
intercostal space or thirteenth rib. The left lateral border is opposite
the eighth rib and intercostal space. The ventral border extends
backward about as far as the umbilicus.
There are no lateral ligaments and the falciform ligament disappears
early.
The =gall-bladder= is attached in the fossa vesicæ felleæ on the right
central lobe, at a considerable distance from the ventral border. The
cystic duct joins the hepatic duct at an acute angle immediately after
the emergence of the latter from the portal fissure. The =bile-duct=
(Ductus choledochus) opens at the papilla duodeni about one or two
inches (ca. 2.5 to 5 cm.) from the pylorus.
[Illustration: