NERVE CELLS OF THE CRAYFISH 53 
normal shape, the cover-glass being supported, while others 
were flattened by pressure upon the cover. In no instance was 
there any indication whatever of Nissl bodies. The cytoplasm 
is quite uniform throughout in its appearance, with numerous 
granules more or less irregular in shape and size and optical 
appearance, distributed with a marked degree of regularity. 
Some of the granules are almost at the limit of vision with the 
2-mm. oil-immersion objective and no. 4 ocular; others are 
much coarser, being several times greater in diameter. In 
shape they vary from almost spherical to an angular outline. 
Some of the granules, at least, are mitochondria, as may be 
demonstrated by staining with Janus green. ‘There is no evidence 
of a grouping of granules into concrete bodies. Intravitam 
staining with methylene blue and with pyronin failed to demon- 
strate any grouping. Nissl bodies are of such size that they 
should be observable if they are present in the living cytoplasm, 
unless such observation is prevented by optical characters. In 
so far as I have been able to observe, they do not exist in the 
living nerve cell of the crayfish as formed bodies. 
The question involved is not as to the existence of Nissl 
substance, but as to the morphology of the substance, whether it 
exists in the condition of dispersed granules or in the form of 
masses, or homogeneously dispersed through the cytoplasmic 
ground-substance. The substance exists in living protoplasm 
but in all probability only in the dispersed condition. 
Golgi internal reticular apparatus 
The Golgi internal reticular apparatus has been demonstrated 
in nerve cells from many sources, by certain technic taking on 
stain and by other technic remaining as clear unstained spaces of 
various sizes and forms. Misch (03) reported some vertebrate 
nerve cells as not showing the presence of the ‘Binnennetz.’ 
Perhaps the results obtained by Misch may be attributed to 
imperfect technic. On the other hand, Cajal (’03) has found the 
apparatus in every type of nerve cell he has examined, and he 
believes it to be universally present in all vertebrate cells. 
THE JOURNAL OF COMPARATIVE NEUROLOGY, VOL. 34, NO. 1 
