62 A. B. MACALLUM. 
come through the corium directly do not branch, are somewhat 
thicker than the others, and have a larger intercellular bead- 
like swelling. These never terminate within the cells and are 
not numerous. All the other fibrils seem to start at the upper 
surface of the corium. I have drawn an exceptional case in 
fig. 1, n”, where a fibril was seen to pass directly through the 
corium and into the axis of a figure of Eberth. One can 
very often see a series of fibrils, at regular distances from each 
other, pass through the corium and terminate at the line 
between it and the epithelium. Sometimes their terminations 
are under the expanded foot of a figure of Eberth which then 
appears to be connected with them. Canini' has drawn a case 
of this apparent connection. 
It must be observed, once again, that the method of staining 
these fibrils is not always successful. Nigrosine stains the 
figures of Eberth, while saffranine attacks the fibrils. If, 
however, the section to be stained be left in the saffranine 
solution too long, the figures take up the colour and have now a 
dull red tint. On the other hand, there is always great diffi- 
culty in preventing all the saffranine from being extracted with 
absolute alcohol. There is another disadvantage frequently 
resulting from the use of this reagent, that the epithelium 
throughout a section does not acquire an equal depth of stain. 
This irregularity, which is referred to by Pfitzner, is, I think, 
not due to any faulty method of manipulation. 
The fibrils which are stained red with: saffranine are nerve- 
fibrils. To prove that they are such it is only necessary to 
treat the epithelium with gold chloride in the manner already 
described. If a thin piece of the tail, prepared in this way 
successfully, be mounted with its epithelium intact, and the 
tube of the microscope be so placed that the superficial layer is 
in focus, such a view is obtained of its cells as is represented 
in fig. 3. Asa rule, the cells appear as there indicated. At 
other times, however, they seem to be made up of polygonal 
fields of bluish-tinted granules, in which the outlines of the 
nuclei are not often visible. Between neighbouring cells can 
1 Op. cit. 
