AUTHOH S ABSTRACT OF THIS PAPER ISSUED UY 

 THE BIBLIOGRAPHIC SERVICE, DECEMBER 15 



THE ISOLATION, SHAPE, SIZE, AND NUMBER OF THE 

 LOBULES OF THE PIG'S LIVER 



FRANKLIN PARADISE JOHNSON 



University of Missouri 



TWELVE FIGURES (TWO PLATES) 



INTRODUCTION 



The following description of the lobules of the pig's liver is 

 based on a study of lobules that were isolated from one another 

 by means of an acid macerating fluid. This method of isolation 

 is invaluable in giving one a correct idea of the shape and size 

 of the hepatic lobule, and in addition, affords a good means of 

 approximately estimating the total number of lobules in the 

 liver. If the maceration is stopped at just the right point, the 

 method permits the easy dissection of blocks of liver tissue. 

 Dissections of injected livers made in this manner, with the blood 

 vessels and bile ducts as little disturbed as possible, give one a 

 clearer understanding of liver structure than can be obtained 

 by any other method. 



A survey of the literature shows that to Wepfer belongs the 

 credit of discovery of the lobule of the liver. In a letter to 

 Paulli (1665) signed by Wepfer, 1664, the substance of the liver 

 was described as follows: 



Examine carefully boiled pig's liver; remove the external membrane 

 and you will find the whole large mass a combination, as it were, of 

 innumerable small glands. Concerning the livers of other animals, I 

 confess, I have not yet made investigations. But upon thoroughly 

 boiling a piece of pig's liver, I have seen small glands, quadrangular 

 and other forms. 



In 1666, Malpighi, unaware of Wepfer's discovery, described 

 the lobular nature of the liver in molluscs, the lizard, ferret, 

 mouse, squirrel, ox and man. Concerning those of man, he 

 states: 



27.S 



