METHOD OF OBTAINING BILE. 177 



liameter of which is about ten times as great as the former, and 

 which have a definite boundary wall, while the bile capillaries 

 have no other boundary than the substance of the liver cell, and 

 therefore are not really vessels. 



These fine intercellular bile passages are described as commu- 

 nicating with the interlobular ducts directly opening into the 

 ducts without any marked increase in the size or change of ar- 

 rangement. The interlobular ducts which follow the course of 

 the artery and portal vein are composed of a delicate basement 

 membrane lined with a thin layer of epithelium, which, in the 

 larger vessels, shows a cylindrical character. The larger bile 

 ducts have a firm, fibro-elastic coat lined with a definite mucous 

 m embrane covered with cylindrical epithelium lying upon a 

 vascular submucosa, in which are scattered numerous glands of 

 saccular form. 



The amount of connective tissue in the liver of man and most 

 domestic animals is very small, but in the pig, bear, giraffe, and 

 some others, it is easily recognized around the lobules, sending 

 delicate supporting processes between the cells of the lobules. 

 It passes into the organ with the portal system of vessels forming 

 a loose sheath derived from the capsule of Glisson, and is dis- 

 tributed with the subdivisions of those vessels to the various parts 

 of the gland. 



The lymphatics are known to be very plentiful, and in intimate 

 relation to the blood vessels. 



Method of Obtaining Bile. For most practical purposes, 

 the bile obtainable from the gall bladder of dead animals is suffi- 

 cient. The bile pigments and cholesterin may be conveniently 

 obtained from the gall stones so often found in the human gall 

 bladder. 



In order to investigate the composition of the bile as it comes 

 from the ducts, before it has been modified by its sojourn in the 

 gall bladder, it is necessary to make a biliary fistula, communi- 

 cating either with the gall bladder or with the bile duct. In this 

 way the rate, pressure, and other points concerning the mode of 

 secretion may be determined. 



