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minutes in celloidin, placed on a cork, and the celloidin hardened in 
75 °/, alcohol in a closed jar, and this jar is cooled either by ice, 
or under a current of cool water, the object being to harden the cel- 
loidin as rapidly as possible. Afterwards, the sections are cut under 
95 °/, alcohol, rapidly dehydrated, cleared in oil of bergamot, and 
mounted in xylol-balsam without cover-slip. 
This method has about the same certainty in tingeing the nerve 
fibres as is usually attained by the rapid silver method, and as al- 
ready mentioned the details are clearer. The process also brings into 
distinct view numbers of the reticulated tissue fibres proceeding from 
the walls of the vessels into the lobules. 
2) The osmium-copper-hematoxylin-method (6). We found in 
nearly all sections treated in this way, numbers of the vascular 
nerves, and even a few of the terminal endings: but unfortunately 
the liver cells would not decolorize with sufficient rapidity, taking 
instead of the usual two or three minutes with the cerebral tissues, 
from fifteen to twenty hours; hence the finer nerves were nearly all 
decolorized , and the method had to be abandoned. Only where the 
sections were sufficiently thin to permit of some details being seen 
after a half-hours exposure to the decolorizer, was anything to be 
done, and naturally the result was very indefinite. No medullated — 
nerves were found in any section examined. 
3) Various gold methods, principally that of Ranvier-Lowit- 
FISCHER, also less concentrated solutions; but except for staining the 
fibres of connective or elastic tissue between the liver cells, the re- 
sults, so far as the nerves were concerned, were negative. Some 
fibres it is true looked like nerves, but on further study with high 
powers, they proved to be other elements. Pictures not unlike those 
of MıurA were obtained without any great difficulty. 
The reticulated tissue. 
One of the most important results accomplished by this study, 
has been the differentiation between the fibres passing off from the 
sheaths of the blood-vessels — portal veins as well as hepatic arteries 
and their branches — and the true nerve fibres, by means of the 
picric acid method. Like all staining with the silver method, this 
tingeing of the vascular fibres is inconstant, perhaps one in five or 
six specimens showing it clearly at some point, in others perhaps but 
faint traces are seen. 
The staining of the proper wall of the vessel differs but slightly 
between portal vein and medium sized arteries. With the first the 
inner circle immediately surrounding the lumen is stained a fainter 
