— 139 — 
dotted substance plenty of fibres of various sizes are seen. The 
greater part of them are extremely slender. In fig. 85 some of these 
fibres from fresh preparations are illustrated. They are present in 
every preparation to unlimited extent, and do not seem to be formed 
in any artificial way, but only to be just isolated. In macerated 
preparations they are still more prominent (fig. 86). They may, 
here, be isolated, and traced for long distances through the dotted 
substance; to some extent, they are of a rather uniform size with a 
small diameter; they have a smooth aspect but may sometimes, 
though seldom, be seen to give off extremely fine lateral-fibrillæ (vide 
fig. 85, 5, e; 86, a, h)\ where such fibrillæ issue small varicose thicken- 
ings are generally present. In thicker fibrillæ subdivisions occasionally 
happen (vide fig. 85, d). It is obvious that a great deal of the thickish 
fibres found in macerated preparations are real nerve-tubes, as they 
may be seen to be direct continuations of nervous processes from 
ganglion cells; these fibres have also, to a certain extent, an aspect 
like what is characteristic for nerve-tubes. To decide the nature of 
the extremely slender fibrillæ, which occur in such abundance, is, how- 
ever, much more difficult; their aspect is undeniably very like that of 
common neuroglia-fibres or connective-tissue fibres; a great many of 
them are so thin that they, even under the highest powers of the 
microscope, appear like lines. As, however, we may find fibrillæ of 
every transition-stage from those finest ones up to these largish 
fibres, which unquestionally are nerve-tubes, and as we may see 
such fine fibrillæ to be given off from these nerve-tubes as side- 
branches, or being formed as a final-product by the breaking up 
of the latter, we feel ourselves forced to define these fibrillæ as 
being to a great extent real nerve-fibrillæ. These nerve-fibrillæ or 
tubes, as we should more properly call them, are certainly of a 
much smaller size than most of the tubes we have hitherto found 
in the dotted substance of other animals; this may, however, be 
accounted for from the smallness of all the nervous elements in 
Patella. 
On the other hand, it is obvious that a great many fibrillæ seen 
in fresh and macerated preparations belong to the neuroglia. Such 
fibrillæ may often be seen to issue directly from neuroglia-cells, or 
united with neurogha-nuclei (vide fig. 79 — 81 ; J^^nn] 82, nc\ 83, n,nc;. 
S6, ne) which occur abundantly in the dotted substance.^) These 
^) The reason why Haller and Maioitz deny the occurence of neuroglia- 
nuclei is, I think, that they have not recognized their real nature and describe them 
as »Schaltzellen« which they believe to be multipolar ganglion cells. H. Schultze, 
Walter, and others have given somewhat similar descriptions. 
