It has been shown by several earlier investigators, using
Feulgen's nuclear reaction, that the chromatin content of the nerve cells is relatively small as compared to that of other cells. Beams ('31, p. 334) says: ". . . . the spinal ganglion cells, like the oocytes (Ludford, '28) show apparently less chromatin material in the nucleus, a s indicated by the Feulgen reaction, than do many other varieties of cells. " His observations do not appear to have brought out information as to the relation of the nucleolus to the little chromatin observed.
Early observers believed the Nissl or "tigroid" material of the cytoplasm of the neuron to arise from the nucleus, probably from the nucleolus itself, and to be actually "chromatin". Thus Dolley ('11) interpreted the changes in the nucleolus and nucleus with the changes in the cytoplasm in fatigue as indications of the gradual exhaustion of a chromatin-forming center. Kreibich ( '16) believed that with a careful staining for Nissl material he could trace delicate strands from the nucleolus, out through the nuclear membrane, to the Nissl bodies themselves.
Later writers (Wermel, '27 ; Loo, '37 ; Andrew, '36) have failed to obtain any reaction whatever from the tigroid material on the application of Feulgen's stain to the nerve cells