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EDMUND B. WILSON. 



D E H 



FIG. 2. Typical reversal, after removal of large chela, X4- 



A, B, C. Reversal in a male, originally left-handed ; result of first moult, eleven 

 days after removal of large chela. A. Cast skin of original small right chela. B. 

 Right chela immediately after moult, showing transformation into hammer-chela well 

 advanced. C. Left chela, immediately after moult, regenerated on the stump of the 

 large chela removed. 



D, E, F. Reversal in a female slightly larger than the specimen shown in A-C, 

 originally right-handed ; result of first moult, sixteen days after removal of large 

 chela. D. Cast skin of original small left chela. E. Left chela immediately after 

 moult, transformation less advanced than in the male. F. Right chela, immediately 

 after moult, regenerated on the stump of the large chela removed. 



G, H. Initial changes in the typical reversal of an originally left-handed male. 

 G. Cast skin of right chela, after first moult, five days after removal of the large 

 left chela. H. The same appendage nine days after the moult, showing remodelling 

 in progress, but still retaining the setose ridge on the dactylus. 



