10 HARRY MILES JOHNSON 



defined by Munk. The details of his report of the operative 

 procedure are as meager as are those of his behavior tests. 



The first operation was the extii-pation of one temporal lobe 

 from an animal whose cochlea on the same side had previously- 

 been destroyed. According to Munk the nervi aciistici make 

 a perfect chiasmus, and this operation should render the animal 

 completely deaf. On the same assumption, if the cochlea on 

 one side were completely destroyed and the auditory area on 

 the same side only partially extirpated, deafness to some tones 

 only — high or deep according as the anterior or posterior 

 region were mutilated — should be produced. Kalischer re- 

 ports, however, that his animals reacted to tones as before, 

 no matter whether extii-pation was partial or complete. There 

 was a noticeable disturbance in responses to commands and more 

 or less disturbance of orientation, but no details beyond these 

 statements are given in Kalischer 's report. 



Before proceeding to extii-pate the opposite temporal lobe 

 from these animals, Kalischer allowed from four to five weeks 

 for recovery, during which he continued his training. He ob- 

 served no change in the animals' discrimination. " Nach der 

 ersten Schlafenlappenextir]Dation hatte sich kein Unterscheid in 

 den Verhalten der Tiere bei der Dressurversuchen gezeigt. Die 

 Tonunterschiedsempfindlichkeit und der Reactionen der Tiere 

 waren die gleichen geblieben, gleichgiiltig, auf welcher Seite die 

 erste operation ausgefuhrt worden war." 



The extiipation of the temporal lobes, Kalischer says, fol- 

 lowed in general the plan of Munk, but sometimes a larger area 

 was removed, both wider and deeper (three-quarters cm. deep) 

 and sometimes opening the ventricle. 



When the second temporal lobe was removed from some ani- 

 mals the visual area also was injured, Kalischer asserts, so that 

 "a part of the peripheral visual field in both eyes was lost."'" 

 After this operation the dogs no longer reacted to spoken com- 

 mands, nor did they show by pricking of the ears or movements 

 of the head any sensitivity to loud noises. Later they apparently 

 began to resume such movements at loud noises and very loud 

 commands, but did not learn to discriminate among them. Be- 

 fore the operation the least whistle or call had been enough to 



** A reliable method of making an accurate test of the dog's peripheral vision 

 would be valuable and interesting. Kalischer does not describe his method. 



