194 Journal of Compauatixe Neukoixxjy. 



In i88c; there appearetl a work bearing the names of Lu- 

 ciani and Seppilli, aheady familiar to specialists by reason of 

 numerous smaller works, which may long serve as a vade 

 mecum for experimenter in this domain. Although almost 

 immediately translated into German(') this work is almost 

 unknown in this country. 



The unwarrantable assumptions of Goltz, which demand 

 positive inhibitory reactions from the injured areas in explan- 

 ation of the restitution of function, and the great diversity 

 in the use of terms led these authors to an analysis of the 

 available methods for determining cortical functions from 

 extirpation, which it may not be useless to repeat. These 

 methods are as follows: 



1. Negative results of extirpation. We may safely and 

 confidently assume that functions not disturbed by the lesion 

 have nothing to do with the area removed. 



2. Comparison of positive effects of extirpation of homo- 

 logous parts. This method suffers from the impossibility of 

 distinguishing the effects of removal of a given area from 

 the accessory disturbance due to the irritation and circulatory 

 disturbances, especially the septic after-effects. The com- 

 parison is also rendered difficult by the variability of the 

 cortical topography even in the same species or sides of the 

 same brain. 



3. Comparison of effects of extirpation of different areas 

 of the cortex. This method is of especial value in determin- 

 ing the extent of the collateral effects, and indicates as a rule 

 that the collateral disturbances usually include functions 

 closely allied to those directly involved in the injury. 



4. Comparison of effects of successive extirpation in the 

 same animal. This method is especially available in the in- 

 vestigation of compensating areas. 



^. Determination of the minimum extirpation producing 



I LuciANNi UND Ski'I'IM, "Die Functions- Localization auf iler (Jrosshirnrinde an 

 Thierexperimenten unci klinischen Fallen naschgewiesen." (German by Fraenkel). 

 Leipzig, 1886. 



