278 "Journal of Coynparative Neurology and Psychology. 



Results. — The results of the present investigation may all be 

 summarized in the following table: 



TABLE IV. 



Showing the Numerical Relations of the II C. Nerve of the White Rat in the 

 Normal Condition and after Section of the Ramus Posterior just Distal to 

 the Ganglion. 



Specimens. 



Normal Rats. 



72 days old (normal) 



72 days old (normal) 



72 days old (normal) 



72 days old (normal) 



72 days old (normal) 



(6) 240 days old, left (normal) . . 



(7) 240 days old, right (normal) . . 

 Rats Operated on at 12 Days of 



and Killed after 60 Days. 



(8) 72 days old (operated) 



(9) 72 days old (operated) 



(0 



(^) 

 (3) 

 (4) 

 (5) 



(10) 72 days old (operated) 



(11) 72 days old (operated) 



(12) 72 days old (operated) 



Rats Operated on at 12 Days of Age 



and Killed after 120 Days. 



(13) 132 days old (operated) 



(14) 132 day sold (operated) 



(15) 132 days old (operated) 



Rats Operated on at 140 Days of Age 



and Killed 120 Days Later. 



(16) 260 days old (operated) 



(17) 260 days old (operated) 



(18) 260 days old (operated) 



Regen- 



Neuroma era- 



TION. 



large 

 large 



partial 

 none 



very small none 

 medium partial 

 large 1 partial 



large 

 very small 



partial 

 ( quite 

 [ perfect 

 small partial 



large none 



small very slight 

 large none 



The weights marked with a star (*) have been calculated from the age, no record having been taken 

 of the body weight in these cases. 



I. Changes Produced by Section of the Nerve ui Young Rats. 



The most interestino; of the observations to be recorded in this 

 place concerns the pronounced cell destruction that occurred in 



