360 USES OF THE LIVER DUCTLESS GLANDS 



spaces between the liver-cells in the lobules open into the interlobular 

 hepatic ducts. It is still a question whether these passages are simple 

 spaces between the cells or true vessels lined with a membrane. 



Anatomy of the Excretory Biliary Passages. Between the lobules 

 the ducts are very small, the smallest measuring about g-J-^ of an inch 

 (8 fji) in diameter. They are composed of a delicate membrane lined 

 with epithelium. The ducts larger than y^Vo" f an mcn ( a out 2O p) 

 have a fibrous coat, formed of inelastic with a few elastic elements, and 

 in the larger ducts, there are in addition a few non-striated muscular 

 fibres. The epithelium lining these ducts is of the columnar variety, 



the cells gradually under- 

 going a transition from 

 the pavement form as the 

 ducts increase in size. In 

 the largest ducts there is 

 a distinct mucous mem- 

 brane with mucous glands. 

 Throughout the extent 

 of the biliary passages, 

 from the interlobular 

 canals to the ductus chole- 

 dochus, are little utricular 

 or racemose glands, vary- 

 ing in size in different por- 

 tions of the liver. These 

 are situated at short in- 

 tervals at the sides of the 

 canals. The glands con- 

 nected with the smallest 



Fig. 76. Bile-capillaries between the liver-cells injected liver ducts are simple follicles 

 of the rabbit, X 500 (Pfeiffer) . 



io of an inch (31 



to 62 ft) long. The larger glands are formed of groups of these follicles, 

 and they measure -%\- or T ^ 7 of an inch (100 or 250 /-i) in diameter. The 

 glands are found connected with the ducts ramifying in the substance 

 of the liver only, and they do not exist in the hepatic, cystic and com- 

 mon ducts. They are composed of a homogeneous membrane lined 

 with small pale cells of epithelium. If the ducts in the substance of the 

 liver are isolated, they are found covered with these little groups of 

 follicles and have the appearance of an ordinary racemose gland, except 

 that the acini are relatively small and scattered. This appearance is 

 represented in Fig. jj. 



The excretory biliary ducts, from the interlobular vessels to the point 



