THE 



Journal of Comparative Neurology. 



Volume X — Number 4. 



THE GIANT GANGLION CELLS OF CATOSTOMUS 

 AND COREGONUS. 



By J. B. Johnston, 



Professor of Zoology, West Virginia University. 

 With Plates XXIV and XXV. 



The giant cells in the spinal cord of fishes have presented 

 great difficulty to impregnation by the Golgi method. I do not 

 know of any description of these cells based on Golgi prepara- 

 tions, and Sargent ('98) states that he tried the Golgi and meth- 

 ylene blue methods exhaustively without results. The follow- 

 ing description is based upon very satisfactory preparations by 

 the Golgi method of the nervous system of embryos of Cato- 

 siomous sp. and Coregonus albus, under 2 cm. in length. 



I shall describe first the cells and their processes in Cato- 

 stomus and then note briefly their special characters in Core- 

 gonus. In sections treated with the Ehrlich-Biondi triple stain 

 these cells stand out clearly on account of their large bodies 

 which are colored red in contrast to the smaller cells whose large 

 nuclei are stained green. In a horizontal section of an entire em- 

 bryo, which fortunately includes the whole length of the spinal 

 cord, 105 of these large cells are to be counted. These prepara- 

 tions show nothing concerning the processes of the cells, but their 

 position is clearly made out. They lie close to the dorsal surface 

 of the cord (frontal or sagittal sections), and at either side of 

 the middle line. Compare Figs. 2 and 3. The bodies of the 

 cells may touch or cross the median plane, but the larger part 

 of every cell lies to one side. At the cephalic end of the cord 

 the cells are found in close proximity to the commissura infima 

 Halleri, which I have described in a paper on the brain of Aci- 

 penser, now in press. In a few cases I have found one or two 



