No. I.] DESMOGNATHUS FUSCA. 259 



difference between the axis-cylinder and protoplasmic processes, 

 basing his opinion not only upon silvered preparations, but 

 upon sections prepared by other methods and upon teased 

 specimens. 



From a series of longitudinal and transections he finds : 

 (i) Cells of the ventral cornua and mesal portion of the my el 

 sending some of their processes into the ventral or anterior 

 commissure and others into the ventral and lateral columns as 

 well as into the ventral roots. (2) Cells of the same horns 

 which lie close up to the lateral columns and send off processes 

 which pass along the inner side of the lateral and ventral 

 columns and bend around in these columns into the ventral 

 commissure and root. (3) Cells of the mesal part whose proc- 

 esses pass off into the dorsal cornua, dorsal columns, and both 

 commissures. (4) Cells of the ventral and mesal part with 

 processes entering into the dorsal and ventral roots. (5) Cells 

 of the dorsal cornua whose processes go over into the dorsal 

 nerve roots and dorsal columns. (6) Cells lying beside the 

 dorsal horns which send processes partly into the dorsal roots 

 and partly into the dorsal columns. 



In the myel of the toad he found (7) some cells sending 

 their processes into the dorsal column and others into the 

 ventral column. (8) Cells of large size lying on the inner side 

 of the white columns sending their processes to the ventral 

 columns and roots, and others to the dorsal, and still others to 

 the lateral columns. (9) Small cells with relatively delicate 

 processes forming partly the dorsal and ventral columns and 

 partly the commissural fibers and nerve net of the gray sub- 

 stance. 



In sagittal sections of the toad myel he noted (10) cells with 

 processes bending around into the dorsal and ventral columns 

 and continuing undivided, or dividing into a cephalic or caudal 

 branch. (11) Cells whose processes passed farther into the 

 gray substance, and on the one hand formed the gray nerve net 

 and on the other enter into the white columns. In frontal 

 sections he finds (12) cells whose processes in part run in 

 toward the central canal and in part to the lateral columns 

 where they may divide, or having divided earlier, send their 



