248 COMPARATIVE PHYSIOLOGY OF THE BRAIN 



But everything requiring associative memory was 

 gone. The dog was not able to seek its food. It 

 recognised neither its master nor its playmates. It 

 could hear but could not discriminate between scold- 

 ing and petting. It was impossible for it to get itself 

 out of any uncomfortable situation. The period of 

 heat was no longer noticeable. The effects are simi- 

 lar to those upon pigeons, with the difference that the 

 secondary effects of the operation on the remaining 

 parts of the central nervous system are greater in 

 dogs. The reasons for this may be purely technical 

 or anatomical, or may be due to a greater sensitive- 

 ness of the central nervous system in dogs. We may 

 mention in this connection that hemorrhages in the 

 human cerebral hemispheres are often accompanied 

 by a complete paralysis of the extremities, while this 

 is never the case in clogs. 



The fact that in animals which normally possess no 

 memory, loss of the hemispheres occasions little dis- 

 turbance, and the fact that in animals possessing 

 memory, the latter disappears upon destruction of the 

 hemispheres, prove that the hemispheres are an essen- 

 tial organ for the phenomena of associative memory. 



4. Pfluger expressed the opinion many years ago 

 that an animal that has lost its brain still possesses 

 consciousness (7). He drew this conclusion from the 

 reactions of decapitated animals. If the tail of a de- 

 capitated eel be rubbed gently on one side the tail 

 presses itself against the finger, but if touched with a 

 burning match it is turned away. From these and 



