MECHANISM OF THE SECRETION OF BILE. " 251 



the fact that the same cells produce glycogenic matter. As 

 far as. we are able to understand the mechanism of secretion, 

 it seems necessary that a formed anatomical element, known 

 as a secreting cell, should elaborate, from materials furnished 

 by the blood, the elements of secretion ; and this cannot be 

 accomplished by a structureless membrane, like that which 

 forms the walls of the bile-ducts. 1 Under this view, assum- 

 ing that bile, as bile, first makes its appearance in these 

 little lobular tubes, the liver-cells are the only anatomical 

 elements capable of producing the secretion. With regard 

 to the mechanism of this secreting action, we have nothing 

 to say beyond our general remarks in the first chapter. 

 With the view we have just expressed, certain elements of 

 the bile are separated from the blood, and others are manu- 

 factured out of materials furnished by the blood by the 

 liver-cells, and are taken up by the delicate plexus of vessels 

 situated between the cells. The discharge of the fluid is 

 like the discharge of any other of the secretions, except that 

 a portion is temporarily retained in a diverticulum from the 

 main duct, the gall-bladder. 



The two distinct functions of the liver now recognized 

 by many physiologists, namely, the secretion of bile and 

 the formation of sugar, have led to the question of the ex- 

 istence in the liver of two anatomically distinct portions 

 or organs, corresponding to its double physiological func- 

 tion. This view, indeed, has been advanced by several 

 eminent anatomists. Robin recognizes two distinct parts 

 in the liver ; a biliary organ and a glycogenic organ. He 

 regards the lobules, with their liver-cells and blood-vessels, 

 as the parts concerned in the glycogenic function of the 

 liver, and the little glands which open into the biliary ducts 

 all along their course (see Fig. 11) and are arranged on 

 the duct "in the form of leaves of fern," as the biliary 



1 An exception to this rule is in the secretion of milk during the period of 

 greatest activity of the mammary glands. (See p. 79.) 



