(i.) 



EXPLANATION OF FIGURES. 



Figs. 1 and 2 (after Fredericq). 



Showing how he explained autotomy in Carcinus 

 moenas by violent contraction of the long extensor, and 

 contact of the distal part of the limb with the carapace 

 or other resistant object. 



Figs. 3 and 4. 



Showing the basal limb -segments in the walking-leg 

 of Homarus vulgaris. 



e = Extensor muscle of segment two. 



/ = Breaking furrow at the central end of segment 

 three. 



