194 Journal of Comparative Neurology. 



In bichromate of silver preparations some of the fibers en- 

 tering from the nerves very quickly break up into branches, but 

 reach a little above the lower half of the ganglion. In a few 

 cases the roots were found impregnated for nearly their whole 

 extent and did not appear to give off many branches to the 

 ventral region. In one case two cells in front of the mandibu- 

 lar nerve were each found connected with a fiber that passed 

 out through the nerve, but whatever inner branches they may 

 have had were not impregnated (PI. XX). In another case 

 a large cell was found on the lower lateral side of the brain 

 sending a process into the region above, where it gave off a very 

 extensive small branch (fig. 36). Near the broken end of the 

 fiber another that is not shown in the figure began. This was 

 apparently a continuation of it. The appearances of the sec- 

 tion indicated that the fiber had been cut on account of its form- 

 ing a slight bend outside the plane of the razor. The second 

 fiber turning forwards gradually became swollen distally and 

 then decreasing passed as a smaller fiber into the root of the 

 antenno-motor nerve. The latter cell then is certainly motor, 

 and taking for granted what has already been fairly well demon- 

 strated by other observers ; namely, that cells in the brain send- 

 ing their neurites out of it are motor or bearers of efferent neu- 

 ral impulses, and the fibers entering from external cells are sen- 

 sory, it is just as surely true that the other cell is of a motor 

 nature. 



This ventral position of motor cells here tends to indicate 

 that the dorsal motor and ventral sensory area of ventral gang- 

 lia, as distinguished by physiologal experiments, is considerably 

 independent of the position of the cell. It may be pointed out 

 that in dorsal lesions it is the connection of the dendrites of 

 motor cells with fibers bearing stimuli to them from other 

 parts of the nervous system that is broken ; while in ventral le- 

 sions it may be the terminations of sensory fibers or of associ- 

 ation cells and their fibers or both that are destroyed. From 

 this it may be seen how indefinite are apt to be results obtained 

 by the physiological vivisection methods. Should experi- 

 ments be repeated with a thorough knowledge of the location 



