ON THE PRESENCE OF THE CENTROSOME IN CER- 
TAIN NERVE CELLS OF THE WHITE RAT. 
By SHINKIsHI Hartat. 
(from the Neurological Laboratory of the University of Chicago.) 
With Plate II. 
In the present paper, the writer describes the appearance 
of the centrosome in certain nerve cells of the white rat. The 
description is presented under the following heads : 
I. Materials used and technique employed in this in- 
vestigation. 
II. The different groups of the cells in which the cen- 
trosome was discovered. 
III. The morphology of the centrosome. 
IV. Historical review of the centrosome in nerve cells: 
V. Summary. 
VI. Illustrations of the centrosome in the nerve cells of 
the white rat. 
I. MATERIALS USED AND TECHNIQUE EMPLOYED IN THIS _IN- 
VESTIGATION. 
The materials used for the present investigation were taken 
from new-born white rats having a body-weight of 4.6-6.0 grams 
and adult white rats having a body-weight of 150 grams. 
Besides these animals, a young mouse (weight unknown) was 
used for comparison. 
Asakilling fluid, the writer’s' new mixture (sublimate-acetic 
formalin mixture) was most frequently used. Besides this, 
1 Hatal, S.—Finer structure of the spinal ganglion cells in the white rat, 
Journ. of Comp. Neurology, Vol. XI, No. 1, 1901, 
