106 COMPARATIVE PHYSIOLOGY OF THE BRAIN 



the mouth-organs, but loses its spontaneity in so far 

 as this is expressed by progressive movements. It 

 will even retain abnormal postures in which it is 

 placed. The operations were performed during the 

 period of heat. Male Limuli that had lost the supra- 

 cesophageal ganglion no longer noticed the females. 

 On the other hand, the legs attempted to remove an 

 irritating object from the surface of the body. De- 

 capitated frogs act in the same way. 



In the cases mentioned above, the Limuli had en- 

 dured the operation well and their wounds were 

 entirely healed. If the cesophageal commissure (c, 

 Fig. 31) be severed on one side, circus-movements 

 will appear in the direction of the injured side, but 

 these only last until the wound is healed. The circus- 

 motions which ensue upon extirpation of one-half of 

 the brain also disappear after a time. If ganglia be 

 removed from the cesophagus-ring, the appendages 

 corresponding to the extirpated ganglia are perma- 

 nently paralysed. 



2. After extirpation of the subcesophageal ganglion 

 (u, Fig. 31) the animal remains extremely quiet, and 

 often lies on the same spot for days. But its respira- 

 tion continues normal, and this proves the erroneous- 

 ness of Faivre's opposed assertion. Except for its 

 immobility and the fact that the extensors of the 

 joint between the thorax and abdomen are paralysed 

 as a result of nerve-injuries, the animal appears 

 normal. 



The four or six ganglia of the abdomen (Fig. 31) 



