34 Journal of Comparative Neurology and Psychology. 



Table II shows (col. E) that when the numbers found in 

 the three nerves of each specimen are combined, the ratios of 

 the sum of the ganglion cells to the sum of the dorsal root 

 fibers show even a less tendency to decrease with increase in 

 the body weight than is manifested when each of the nerves is 

 considered separately as in the previous table. Indeed, two of 

 the three cases in which the sum ratio is highest are in the two 

 largest specimens. • The sum ratios of cells to fibers on the dis- 

 tal side of the ganglion (col. F) follow so closely the variations 

 of the ratios dealing with dorsal root fibers that whatever is 

 true for the one is practically true for the other. 



By comparing columns E and F it is seen that in the sums 

 of the cells and fibers in the three nerves of the several frogs, 

 the number of cells per fiber on the distal side of the ganglion 

 is only from 0.2 to 0.7 of a cell less than on the central side. 

 The cases in which the difference is greatest are in the largest 

 specimens. The average difference is 0.6. In was seen in Table I 

 that when the Vth nerves alone are considered this difference 

 averages i.i cells, being less in the Vlth and much less in the 

 IXth nerves. 



In columns B and H, Table II, better than Table I, is also 

 illustrated the fact that the relative number of cells and fibers 

 apportioned to a given nerve varies greatly. To the unaided 

 eye the Vth nerve usually appears smaller than the Vlth, but in 

 three of the seven frogs here it contains appreciably more cells 

 and fibers than the Vlth. This variation from the usual pro- 

 portion is more frequent in the IXth nerve but its variation is 

 less manifest here because of the absence of figures for the nerves 

 adjacent to it. The relatively large sums for the 7 gram frog 

 are due to its having comparatively a much larger IXth nerve 

 than usual for its weight. Also the IXth m the 25 gram frog 

 seems to have been small. In column I it is seen that the num- 

 bers of dorsal root fibers vary much as the ganglion cells and as 

 the fibers on the distal side of the fjang-lion. 



