44 res. ROSS 
which to all appearances, without seemingly leaving the region, pass to 
one dendrite or another. Further, there is a submarginal delicate 
concentric zone that colors less intensely with silver, in which in a good 
preparation there may be discovered a complex network of fine filaments, 
pale, rather thick and circumscribed polygonal meshes. The compari- 
son of these preparations with those obtained by Nissl’s method shows 
that the zone is principally of chromatic granules. This has been well 
studied and described by Studni¢ka. Jmmediately following, a fibrillar 
zone is evident, consisting of dense bundles of unequal thickness, dense, 
concentric, extending through a great part of the protoplasm. The 
fibrillar layer is almost always discontinuous; often its bundles double and 
pass to a deeper layer of whorled and spiral appearance, previously 
observed by authors and especially by Studni¢ka. At the level of the 
zone the granules of Nissl are absent or are limited in number. Yet 
it is most interesting of all that its fibers unite at an angle of the soma, 
become very pale and delicate (usually appearing redder and clearer 
than the remainder of the reticulation) and producing the principal 
contingent of the axone. A section somewhat tangential reveals the 
whorls that the bundles of the layer describe, as well as the complica- 
tions of their deep derivation. For underneath the aforesaid fibrillar 
mass we find a thick, irregular layer of bundles, disoriented, and con- 
stituted principally of a reticulation similar to that of the second zone. 
And finally around the nucleus we observe an obscure capsule composed 
of compact primary filaments arranged in a dense network which 
recalls completely the pattern (emplazada) underneath the cellular 
membrane. 
Text figure 19 of Tello’s description shows an encircling intra- 
cellular axone, and figure 20 shows a whorled condition of fibrils 
similar to the appearance of figures 5 and 6 of my 1915 paper. 
Heidenhain (’11) describes a similar arrangement ofneurofibrils 
in certain spinal ganglion cells of the frog. 
OBSERVATIONS AND DISCUSSION 
Intracellular axone and neurofibrillae 
Since Apdthy’s work revived the interest in the fibrillar 
structure of nerve cells there has been much controversy as to 
the relations of the axone fibrils within the perikaryon. This 
has centered naturally about the possible function of these 
fibrillar structures. Are they the conducting substance par 
excellence? Are they morphological expressions of the stresses 
and strains in the ground-substance indicating the direction 
