940 THE EXTERNAL SECRETIONS 



with one another at the periphery of the lobule as well as near the 

 hilum. 



The Function of the Liver. While we are chiefly concerned at 

 this time with the external secretion of the liver, known as the bile, 

 it should not be forgotten that this organ performs several other im- 

 portant functions which may be briefly summarized as follows: 



(a) It furnishes an internal secretion which is concerned with the metabolism 

 of the carbohydrates. Sugar is deposited in the hepatic cells in the form of gly- 

 cogen, which is later on reconverted into sugar. 



(6) It forms those bodies which are subsequently abstracted by the cells of the 

 kidney and appear in the urine in the shape of urea and allied substances. 



(c) It is the principal organ in which the red blood-corpuscles are destroyed. 



(d) It plays an important part in the coagulation of the blood, because it gives 

 rise to anti-coagulating substances. 



FIG. 501. LIVEK CELIS CONTAINING GLYCOGEN. (Barfurth.) 



(e) While its external secretion, the bile, possesses an important digestive 

 action upon the fats, it is also a natural antiseptic, an excretory medium, and a 

 stimulant of peristaltic activity. 



(/) It is the chief heat-conserving organ in our body, and probably also 



(g) The principal formant of lymph. 



The Characteristics of Bile. The quantity of bile which is se- 

 creted by an adult of medium weight in a day, has been estimated at 

 500 to 1000 c.c. It is not difficult to obtain it, because the establish- 

 ment of a fistula of the common duct or of the fundus of the gall- 

 bladder is frequently undertaken to-day for the relief of the symptoms 

 following the obstruction' of these passages by calculi or by malignant 

 growths affecting the pancreas and neighboring orifices of the duct of 

 Wirsung and common bile duct. Bile may also be obtained from the 

 gall-bladder after death, but if removed days later, it may have lost its 

 normal characteristics altogether. In the dog, Pawlow advises to 

 establish a biliary fistula by excising the entire segment of duodenum 

 in the immediate vicinity of the orifice of the common duct, and fasten- 

 ing it to the edges of the wound in the abdominal wall. 



