REVERSAL OF ASYMMETRY IN ALPHEUS. 



I 99 



reversal occurs) but the two are of nearly equal size. The 

 species I have studied agrees in showing no reversal after this 

 operation, but the hammer claw is from the first in most cases 

 very distinctly larger than the other ; though as was to be ex- 



A 



B 



D 



FIG. I. Normal and regenerating chelae of Alpkeus fitter ochelis, X 4- 



A, B. Left and right chela? of male ; d. s., setose ridge of dactylus, p. s., setose 



ridge of propodus ; h, hammer ; g, transverse groove, only faintly indicated in the 



small chela. 



C. Chelae regenerating without reversal, after removal of both appendages from a 

 left-handed specimen ; immediately after first moult, twelve days after operation. 



D. Chelae of originally left-handed individual, regenerating very slowly without 

 reversal after removal of both chelae ; eleven days after operation. 



E. Regenerating chelae of originally left-handed individual, three days after re- 

 moval of both chelae. Differences of the chelae already apparent; no reversal (the 

 appendages are viewed from the lower side and hence appear reversed as compared 

 with the other figures). 



