478 
DR. C. HANDFIELD JONES ON THE 
the wall of the ducts, preserving still the general outline ; it seems therefore certain 
that the basement membrane is only a temporary structure, which disappears when 
the cells are actively discharging their contents. A forcible and instructive contrast 
to the above condition was exhibited by a liver which I examined, which was in an 
advanced stage of fatty degeneration ; in this the linear arrangement of the cells was 
lost ; they lay confusedly together, and were gorged with their fatty contents ; the 
margin of the lobule, far from exhibiting any tendency to discharge the retained 
secretion, was invested, and, as it were, closely bound by a membrane, not of the 
delicate transparent texture of the basement tissue, but much more opake, and closely 
resembling the semi-fibrous aspect of thin layers of false membrane*. I may here 
observe that I have not been able to find any epithelium lining the interlobular ducts ; 
the basement membrane, where it exists, appears quite bare, and through its trans- 
parent texture the terminal cells can be plainly discerned with their granular or oily 
contents; this is not in accordance with Mr. Bowman’s opinion, who considers “the 
epithelium of the lobules to be continuous with that of the ducts from this how- 
ever I am led, both by observation and the bearing of the facts now related, to dis- 
sent : it then becomes a question, in what manner does the epithelium of the larger 
ducts terminate ? This is difficult to determine, but I am inclined to think that it 
serves only as a lining to those ducts which have no secreting parietes, and that in 
these it supplies the mucous secretion, with which we know they are lubricated. In 
the gall-bladder of a sheep examined immediately after death, the basement mem- 
brane of the plicae was found to be beset with particles which had not the usual finely 
mottled aspect of columnar epithelium, but seemed to be composed of very minute 
globules ; in a short time these dissolved away into an amorphous matter. In the 
hepatic duct the epithelial particles were very small, about 7 oVo th of an inch in dia- 
meter ; these also disappeared very soon ; the general surface was covered by a great 
number of globules considerably larger, hut of very various size, which closely 
resembled the mucous globules in the secretion of the nose or pharynx. A similar 
appearance was observed in the hepatic duct of a dog, where after a very short time, 
the epithelial particles covering the surface became converted into groups of minute 
globules ; according to this view, the excretory part of the duct would have its own 
peculiar protecting epithelium, preparing the surface for the passage of the bile 
furnished by the secretory portion'!'. 
From all the facts which have been now related, it may, I think, be concluded, 
that the cells forming the margin of the lobule are those in which the elaboration 
of the secretion is perfected, and that as this is effected, they burst and discharge 
* In cases of this kind the primary cell membrane is often seen to be manifestly altered, appearing striated 
and of a coarser texture. 
f I have ascertained subsequently, by examination of perfectly recent specimens, that there is occasionally 
a layer of epithelium on the free surface of the basement membrane, but it is extremely delicate when it exists, 
is often absent, and does not appear to be in any way continuous with the secreting epithelium of the lobules. 
