8 Cincinnati Society of Natural History. 
This bead or neurosome has peculiar chemical affinities for 
the staining fluids. Eosin or erythrosin stain this element 
very deeply, so that it can easily be distinguished from the 
rest of structures. The fine filament joining these beads 
seems to be slightly different from the neurosome itself, as is 
shown by a slightly different staining reaction. It seems, 
indeed, that these neurosomes are a highly differentiated 
portion of the protoplasm which forms the reticulum. 
The form and size of the neurosomes are different in 
different localities, as has been already described by Held. 
These structures are especially numerous within the axone 
hillock and intracellular extension of the axone. At the 
periphery of the spinal ganglion cells, the individual meshes 
of the reticulum are so large that the neurosomes are less 
crowded, hence, in this region, they are scattered very irregu- 
larly. But on the contrary, in the remaining parts of the 
cell, the meshes of the reticulum are elongated in shape and 
the rows of neurosomes become more crowded together, thus 
giving the fibrillar appearence. At first glance, this arrange- 
ment of neurosomes looks very much like the fibrils which 
have been described by many authors. Careful observations, 
however, show that these lines appearing like fibrils are 
composed of a row of minute beads arranged serially. 
Moreover, these pseudo-fibrils are connected by protoplasmic 
threads, thus forming the reticulum. This structure is shown 
in Fig. 7. Around the nucleus these neurosomes form some- 
what concentric lines in a very beautiful. manner. But 
gradually the figure becomes irregular as the reticulum 
approaches the periphery. ‘This is the appearance generally 
found in the spinal ganglion cells. Sometimes the cell shows 
different arrangement of neurosomes, namely, concentric 
lines at the periphery but not in the neighborhood of nucleus. 
Still other variations in arrangement are found. 
Graf (*) noticed the fibrils which are composed of a row of 
minute beads, in the Purkinji cells of human cerebellar cor- 
tex. Hesaid: ‘The cytoplasma show the most beautiful 
fibrillar structure that I have ever seen. The fibrille are 
! 
*) Graf, A—On the use and properties of a new fixing fluid (chrom - oxalic.) — 
Bull. of Pathol. Institute of the New York Hospitals, ’97. Vol. II, p. 386. 
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