468 
DR. E. KLEIN. 
be traced for a very considerable distance,even through several 
fields of the microscope. On theirway they give off right and left 
similar horizontal fibrils; everyone of them, if long enough, can 
be seen to change repeatedly its level, now ascending to almost 
the free surface, then, again, dipping down and pursuing its 
course among the middle layers of the epithelium. In this 
manner they form a very intricate texture, such as 1 have 
figured ill my -former papers, and as is also figured by 
Hoyer in his fig. 2, plate xiii. We find these fibrils in all 
layers, between the most superficial layer of scales and the 
deepest layer of columnar cells, and I must, therefore, correct 
accordingly my former statement as to the presence of these 
fibrils only in two layers (a deep and superficial intra- 
epithelial network), although I must adhere to my former 
statement that they are most numerous in the superficial 
layers. The fibrils are of various thicknesses ; some are con- 
spicucusly thicker than those of the subepithelial network. 
This is especially the case with those in the superficial layers, 
as I must persist in maintaining against Hoyer (1. c., p. 234) ; 
but in all layers in which they occur we find fibrils of com- 
paratively great thickness crossing and anastomosing or 
giving off respectively fibrils of such fineness that it is just 
possible to trace them. Whether very fine or not, they almost 
invariably possess minute varicosities, some fewer, others 
more ; especially the very fine ones show them better and 
more regularly disposed than the thick. Besides these fine 
varicosities there are other larger ones more irregularly 
distributed. They are either staff-shaped, or spherical, 
or pear-shaped, or angular. Any of these large vari- 
cosities may be met with in the course of the fibrils 
where they join others or where they give off one or two 
lateral branches, or they occur at the apparent extremity of a 
fibril. I say purposely apparently,” since we shall presently 
see that they are not the real ends. Such apparent ends 
occur on the fibrils or their branches in all layers, as Cohn- 
heim very correctly described (1. c., p. 28), except, of course, 
the deepest layer of columnar cells, and the most superficial 
one of fiattened scales. 
The nerve-fibrils do not pass into this last-named layer, and certainly do 
not extend beyond it. 1 have expressed myself in the same sense already in 
my former communications, in accordance with Kolliker. Hoyer and 
Izquierdo did not see them pass into the most superficial layer of scales. 
When looking at a horizontal section comprising the complete epithelium, 
it will at first appear as if some of the most superficial intraepithelial 
fibrils did really extend as far as the free surface. To determine this it is 
necessary to use high powers, such as Zeiss’s yV oil immersion, or Hartnack’s 
10 immersion ; it will then be seen that one layer of nuclei {i.e. those of 
