be served. So from my cabinet of instruments I 

 selected a sharp knife having a needle-like blade 

 with a recurved point. This keen hook I introduced 

 into the gaping wound on the under part of the 

 shell, and with a single stroke severed the two 

 nerve trunks communicating between the sub- 

 esophageal ganglion and the brain. The result of 

 this operation was practically to isolate the brain. 

 With its connectives cut, this organ was rendered 

 as useless as if it had been removed from the body. 

 All consciousness was completely gone; whatever 

 movements the crab would now exhibit would be 

 the sole result of reflex. 



To say nothing of the shock of such an operation 

 during so delicate a period, it should seem that 

 Jim could not survive by many hours the mangling 

 he had received on the casting of his molt. Yet two 

 days later when I looked into the small tank into 

 which I had placed him by himself, he was still 

 alive. Indeed, there were signs of returning 

 strength; his shell had hardened; he had moved 

 from the spot where he was put. Nor was this all. 

 He had made some attempt to disguise himself. 

 For attached to the margin of his carapace, I found 

 a slender raveling of seaweed — a crumpled frag- 



[247] 



