462 
DR, E. KLEIN. 
but in most cases remain in the same level, h. Fibrils which 
take a long and wavy course^ altering their direction and 
level many times^ running repeatedly upwards or dowmwards 
in a vertical direction. In sections that are placed horizon- 
tally, and comprise the anterior layers of the cornea, these 
fibrils can be traced in their entire course, but it requires 
great attention to follow them through all their changes of 
level. 
Now, the nerve expansion that Hoyer called the sub- 
basilar plexus can be separated into the following three 
systems : — 1. A plexus of thicker and finer fibrils, which lie 
in the same level as the most anterior branches of the 
stroma plexus, that is, immediately behind, and closely to 
Bowman’s membrane. This system we call the suhhasilar 
plexus proper. The thicker fibres of this system branch, 
and they and their branches run a more or less wavy 
course. The finest fibrils of this system pass out of this 
level behind or in front. 2. From the branches of the 
stroma plexus we trace fine fibrils, which at once pass into 
the layers behind, and here run for a long distance in 
straight lines ; they branch repeatedly and anastomose by 
these branches in rare places wdth similar fibrils ; they ter- 
minate apparently in the corneal substance with free ends. 
These fibrils constitute the deep subbasilar fibrils. We 
shall return to them below. As mentioned just before, 
some of the fine fibrils of the first system leave the level of 
this latter, and run behind it as straight fibrils identical 
with those of the second system. 3. From the level of the 
first system fine fibrils pass anteriorly into the basement 
membrane ; here they may be followed in their winding 
course for a long distance, changing their direction repeat- 
edly ; they are not very numerous, and within this mem- 
brane may be seen to branch here and there. These fibrils 
may be called the intrabasilar fibrils. They and their 
branches have a tw^o fold destination : a, either they again 
pass backwards and associate themselves to the deep sub- 
basilar fibrils, or, as is not unfrequently the case, they pass 
anteriorly through the basement membrane and enter the 
subepithelial network to be described presently. In the 
Plate XXXVII, accompanying this paper, I have given 
an accurate representation of these different fibres in figs. 
1—3. • 
The nerve-fibrils in the immediate proximity of the epithe- 
lium form what is known as the subepithelial netw'ork ; it is 
made up of fine and finest varicose fibrils, and they are derived 
from two sources : — (< 7 ) from the ratni perforaiites ; this source 
