134 



THE FROG 



CHAP. 



channels or bile-passages (c. b, b. P). These are found to 

 open into one another, and finally to discharge into 

 definite tubes (B, d), lined with epithelium. These, in 

 their turn, unite into larger and larger tubes, which 



FIG. 42. A, portion of a section of the Frog's liver ( x 350) ; B, small portion of the 



same, showing the origin of a bile-duct. 



bl. blood-capillaries ; b. p., c. b., c. b', c. b", bile-passages ; c. b'", the same in trans- 

 verse section ; c., hp. liver-cells ; d. smallest bile-duct ; nc, nu. nuclei. (A, 

 after Howes ; B, after Hoffmann.) 



form the hepatic ducts and ultimately open into the 

 common bile-duct (p. 68). 



The liver-cells are glandular and secrete the bile, 

 which, as it is formed, exudes into the bile-passages and 



