| THE LIVER. 1065 
to the right, from the middle of the longitudinal fissure, between the quadyrate 
lobe in front and the caudate and Spigelian lobes behind (Fi ig. 716). Through it’ 
the portal vein, hepatic artery, and hepatic plexus of nerves enter, and the hepatic 
ducts and lymphatic vessels leave, the liver, whilst around its margins are attached 
the two layers of the lesser omentum. The fissure itself is filled, between the 
entering and issuing vessels, by a loose connective tissue known as Glisson’s 
capsule, which passes with the portal vein into the liver substance. 
When the liver is in the body, or when hardened before removal, these three fissures, instead of 
appearing as wide, shallow depressions, have the form of narrow ‘clefts, with a depth of three- 
quarters to one inch (18-25 mm.), or even more—a form which results from the folding together of 
the portions of the liver hounding these fissures. 
(4) The fossa of the gall-bladder (fossa vesicve fellew) is a slight depression 
which begins (often as a notch) at or near the inferior border of the liver, 
and runs backwards and to the left, as far as the portal fissure (Fig. 716), 
Separating the quadrate from the rest of the right lobe. Its surface is uncovered 
by peritoneum as a rule, and in it lies the gall- bladder—the two being united by 
areolar tissue. 
(0) The fossa of the vena cava (fossa ven cave) is a deep groove, on the 
back of the liver, between the Spigelian and right lobes, in which the upper 
part of the inferior vena cava is embedded, immediately before it pierces the 
diaphragm. It has been already described in connexion with the posterior area of 
the parietal surface of the liver, page 1061. 
The depressions for the gall-bladder and the vena cava are called, almost indiscriminately, 
fissures or fossee. In hardened specimens, it will be seen that only three are really fissure or 
crevice-like, namely, the umbilical fissure, the portal fissure, and the fissure of the ductus venosus : 
the remaining two are rather of the nature of fossee. 
Lobes of the Liver.—The liver is divisible into two chief lobes, right and 
left, which are separated by the attachment of the falciform ligament above and in 
front, and by the two parts of the longitudinal fissure below and behind. The right 
lobe forms about four-fifths of the mass of the liver, and on it three secondary lobes—_ 
the quadrate, Spigelian, and caudate, already sufficiently described—are marked off 
by the five fissures referred to in the preceding paragraphs. The left lobe is much 
smaller and more flattened than the right, and, as a rule, it projects one or two inches 
(2°5 to 5-0 em.) to the right of the middle line. The details of these lobes have been 
already given in connexion with the surfaces of the liver. 
Peritoneal Relations of the Liver.—With the exception of (1) the uncovered 
area at the back of the right lobe, (2) a small triangular space on the parietal surface, 
where the two layers of the faleiform ligament separate posteriorly, and (3) usually, but 
not invariably, the fossa of the gall-bl: udder, the liver is completely covered by peritoneum. 
The covering of the caudate and Spigelian lone is derived from the small sac, that of the 
rest of the organ from the great sac of the peritoneum. 
The peritoneum of the anterior abdominal wall passes back on the under surface of 
the diaphragm, whence it is reflected on to the upper aspect of the liver, but the line of 
reflection is broken by a fold running down at right angles from its middle to the umbili- 
‘al notch ; this is the faleiform ligament already referred to. The portion of the reflection 
to the right of this fold forms the upper layer ‘of the coronary ligament, that to the left 
forms the upper layer of the left lateral ligament. 
Having thus reached the liver from the diaphragm the peritoneum passes forwards, 
clothing its parietal surface as far as the anterior margin, around which it turns to gain 
the lower or visceral surface. This it also covers as far back as the portal fissure and. the 
fissure of the ductus venosus (Fig. 716), from which it descends to the stomach as the 
anterior layer of the lesser omentum. 
As regards the covering derived from the small sac :—Its peritoneum passes in through 
the foramen of Winslow, which is placed immediately beneath the caudate lobe, and thus 
it clothes this lobe (Fig. 716). Then turning upwards it expands over the Spigelian 
lobe, clothing its two surfaces. 
From the right margin of the Spigelian lobe it is reflected to the diaphragm, here 
a. 
