1898-99. | STRUCTURE, MICRO-CHEMISTRY AND DEVELOPMENT OF NERVE CELLS. 415 
alkalies should remove the granules, leaving vacuoles, but not the 
nucleolus or the oxyphile nuclear substance which are related sub- 
stances. 
The slight degree of alkalinity necessary to alter the granules 
suggested that the blood, which is really more alkaline than some of the 
solutions used, might act in a similar way. This was tried and found to 
be the case. After loose sections of a spinal ganglion that had been 
fixed in alcohol had been in fresh défibrinated ox-blood for twenty 
hours, the granules were altered in the same way as if they had been in 
potash or soda solutions for the same time. We thus find that the gran- 
ules, as they occur in the cells after fixation, are altered by the animal’s 
own blood. 
Eve observed that salt solutions had little action on the granules, but 
Bihler found the granules were soluble in physiological salt solution in 
twenty-four hours, leaving vacuoles in the cell. My results coincide with 
those of Eve, for when fresh spinal cord and ganglia were left in salt 
solutions for as long as three days at room-temperature the substance of 
the Nissl granules was still present. The cells contained vacuoles, 
forcing the granules into distorted shapes, but the substance stained 
normally with toluidin blue, and contained iron. In one case, after 
material had been in the salt solution for three days, the granules were 
so altered that they would not stain with toluidin blue. On examina- 
tion the salt solution used was found to be distinctly alkaline, but in all 
cases where neutral salt solution was used the substance of the granules 
was not removed. , 
Leaving fresh material in distilled water for five days at the tempera- 
ture of the room does not alter the staining powers of this substance, 
although the cell may contain vacuoles. Hardening material, however, 
by putting it into boiling water, has an action on nerve cells somewhat 
similar to the action of dilutealkalies. If the boiling has been continued 
long enough the granules will not stain with basic dyes and the iron 
cannot be detected in them with the acid alcohol method. The distri- 
bution of phosphorus is, however, normal throughout the cell. 
Held failed to obtain a Millon reaction in the granules. A Millon 
reaction may, however, be obtained throughout the cell body, the 
nucleolus and oxyphile nuclear substance, if sections of material fixed 
in alcohol are left in freshly prepared Millon reagent for several hours 
at room temperature. 
Besides the granules, the nerve cells frequently contain a yellowish 
