TERMINATION OF NERVES OF MAxMMALIAN CORNEA. 
475 
some cornese in a greater or smaller portion, the corneal cor- 
puscles and their processes are of a deep reddish-purple or 
reddish-black colour, while in others the corneal corpuscles 
are hardly at all stained, or only of a light grey or bluish- 
grey colour. The same difference may occur in one and the 
same cornea, and, of course, we then find zones of transition 
of the former into the latter. Let us take a cornea in 
which the corneal corpuscles and their processes are con- 
spicuously brought out, and well and deeply stained, and let 
us add that in the majority of these instances also the fine 
nerves are well stained, i.e. of the same deep colour as the 
corpuscles aud their processes. And let us bear in mind 
that the nerve-fibres are situated in the lymph-canalicular 
system which also contains the corneal corpuscles and their 
processes. Let us further bear in mind that these nerve- 
fibrils and their branchlets run out close to the corpuscles 
and their processes. Under these circumstances nobody will, 
I think, be in a difficulty to explain the above-mentioned 
connection of the nerve-fibrils with the corneal corpuscles. 
Supposing in the preparations represented in fig. 4, 4a, 5, 
and 6, the corneal corpuscles were as deeply stained and of 
the same colour as the nerve-fibrils, nobody could fail to find 
here connections between the former and the latter ; and, 
indeed, in the very same specimens from which these draw- 
ings were made there are places in which, owing to the deep 
colouration of the corneal corpuscles and their processes, the 
distinction between them and the fine nerve-fibres is lost, 
and, therefore, an apparent connection between them is 
found to exist. It is quite clear that such places are useless 
for determining the relation between the nerve-fibrils and 
the cornejil corpuscles, and it is to me inexplicable how 
Izquierdo omitted to bear this in mind, since Hoyer (1. c., 
p. /^41) had already drawn attention to the great importance 
of having specimens in which the corneal corpuscles and 
nerve-fibrils are of a different colouration. Izquierdo^s 
drawings (plate i, figs. 1, 2, 3, and 4), leave no doubt that 
lie had to deal with specimens in which the corneal cor- 
])uscles and their processes and the nerve- fibrils were very 
deeply and uniformly stained. For this reason, then, his 
assertion about the direct connection of the processes of the 
corneal corpuscles with the fine nerve-fibrils, and conse- 
quently also Waldeyor’s summing up (1. c., p. 378) based 
u])on it, loses the value attributed to it. 
