510 M, J. GREENMAN 



12. The increase in number of fibers on the distal side of the 

 lesion is less than on the proximal side but the number always 

 exceeds that found on the control side. 



13. The number of regenerated fibers rapidly increases as the 

 region of the lesion is approached from the proximal side; the 

 number decreases as we pass from the lesion distally. Over 13 

 per cent of the regenerated fibers arise from a point more than 

 7 mm. above the lesion. 



14. The average sectional area of the 10 largest fibers in the 

 middle zone of the peroneal nerve of a normal albino rat of 135 

 grams body weight was found to be 113.6 square micra. 



15. The nerve, fiber tapers from its proximal to its distal end 

 (see table 9). The sectional area of fibers increases with the 

 age of the animal during the first 276 days of life. 



16. The average sectional area of the 10 largest fibers from 

 the control nerve of an operated albino rat of 156 grams body 

 weight is 65.7 square micra. 



17. One of the results of operation is, therefore, a loss in sec- 

 tional area of nerve fibers of the control nerve. In this instance 

 the loss amounts to 42 per cent. It is possible that this effect 

 is general throughout the peripheral nervous system. 



18. The sectional area of the 10 largest nerve fibers on the 

 proximal side of the lesion is 55.8 square micra, or 15 per cent 

 less than the area of the fibers of the control nerve. 



19. The sectional area of the 10 largest regenerated nerve fibers 

 on the distal side of the lesion is 29.9 square micra or 54 per 

 cent less than the area of the fibers in the control nerve. 



20. In the normal albino rat of 135 grams body weight, the 

 axis-sheath relations of the fibers of the peroneal nerve are as 

 follows: Area of axis 51.8 per cent. Area of sheath 48.2 per cent. 



21. In a series of three operated animals of an average weight 

 of 156 grams, the average axis-sheath area relation is as follows: 



Controls Axis 44.3 per cent Sheath 55.7 per cent 



Proximal end of operated 



nerve Axis 40.3 per cent Sheath 59.7 per cent 



Distal end of operated 



nerve Axis 45.8 per cent Sheath 54.2 per cent 



