236 Jimrnal of Comparative Neurology and Psychology. 



\\\ the following figures (8-3S), are given the projections of the 

 ventral roots of the left spinal nerves of man. Their magnification is 

 33 diameters. Within the outlines of each fascicle are found two 

 numbers : the first designating the number of the fascicle, and the 

 second the number, in thousands, of the nerve fibers per sq. mm. of 

 its cross-section. Thus, in C. I the first fascicle has 12.3 thousands, or 

 12,300 nerve fibers per sq. mm. of its cross-section. In a few of the 

 outlines of the fascicles is found a letter "c." This is to signify that 

 the fascicle was found to be cut obliquely, and that the number indi- 

 cating the nerves per sq. mm. is that of some neighboring fascicle sim- 

 ilar in constitution, and that the corrected area of this fascicle was ob- 

 tained by dividing the number of fibers in the fascicle by this number 

 per sq. mm. The outlines are always those of the ////(V/vrr/t'^ projec- 

 tions. In the Tables VIII-XXXVIII accompanying the projections 

 are found the data for each root. These tables have four columns of 

 figures. In the first is found the number given to each fascicle ; in 

 the second the area in sq. mm. of the cross-section of each fascicle; in 

 the third the number of nerve fibers counted in the cross-section of 

 each fascicle ; and in the fourth the number, in thousands, of nerve 

 fibers per sq. mm. of the cross-section of each fascicle. In cases where 

 a fascicle was found to have l)een cut obliiiuely and its area has been 

 corrected, the number indicating the corrected area is placed in the 

 column itself and the number indicating the uncorrected area after it 

 in parenthesis. At the bottom of the table are found the totals. 

 These totals have been brought toy-ether in Table II. 



