OBVIOUS STRUCTURE OF THE LIVER. 349 



OBVIOUS STRUCTURE OF THE LIVER. The substance of the liver Lobuiar 

 consists of small masses called lobules, together with vessels which 

 are concerned both in the production of the secretion, and in the 



nutrition of the organ. The whole is surrounded by a fibrous and encased by 



J two coats. 



a serous coat. 



Serous coat. The peritoneum invests the liver almost completely, Serous coat, 

 and adheres closely to the fibrous coat. At certain spots intervals 

 exist between the two, viz., in the fissures occupied by vessels, along where 

 the line of attachment of the ligaments, and at the surface touching 

 the gall-bladder. 



The fibrous covering is very thin, but it is rather stronger where Fibrous 

 the peritoneum is not in contact with it. It invests the liver, and 

 is continuous at the transverse fissure with the fibrous sheath into the 

 (capsule of Glisson) surrounding the vessels in the interior. When interior - 

 the membrane is torn from the surface, it will be found connected 

 with fine shreds entering into the liver. 



Size and form of the lobules. The lobules (fig. 132, I) constitute Lobules of 

 the proper secreting substance, and can be seen either on the 

 exterior of the liver, on a cut surface, or by means of a rent in 

 the mass. As thus observed, these bodies are about the size of a size and 

 pin's head, and measure from ^jth to ^th of an inch in diameter. appe 

 Closely massed together, they possess a dark central point ; and form ; 

 there are indications of lines of separation between them, though 

 they are to some extent united together. By means of transverse 

 and vertical sections of the lobules, their form appears flattened on 

 the exterior, but they are many-sided in the interior of the liver, position to 

 They are clustered around the smallest divisions of the hepatic 

 vein, to which each is connected by a small twig issuing from the 

 centre, something like the union of the stalk with the body of a 

 small fruit. 



VESSELS OF THE LIVER. Two sets of blood-vessels ramify in the Vessels in 

 liver : One enters the transverse fissure, and the branches are tb 

 directed transversely in spaces (portal canals) where they are 

 enveloped by areolar tissue. The other set (hepatic veins) runs from 

 the anterior to the posterior border of the liver for the most part 

 without a sheath. The ramifications of these different vessels are to 

 be followed in the liver. 



The capsule of Glisson is a layer of areolar tissue, which envelops Capsule of 

 the vessels and the ducts in the transverse fissure, and is continued G1 

 on their branches in the portal canals. In this sheath the vessels 

 ramify, and become minutely divided before their termination in 

 the lobules. If a transverse section is made of a portal canal, the 

 vessels will retract somewhat into the loose surrounding tissue. 



The portal vein ramifies in the liver like an artery ; and the Portal vein 

 blood circulates through it in the same manner, viz., from trunk 

 to branches. . After entering the transverse fissure the vein divides occupies 

 into large branches ; these lie in the portal canals or spaces, with 

 offsets of the hepatic artery, the hepatic duct, and the nerves and 

 lymphatics (fig. 132, p). The division is repeated again and again 



