EXPLANATION OF PLATE VIII. 



FlGUKE 3G. Squilla einpusa Say, (p. ;">:}(.; ;) lateral virw of the free-swimming larv 



in one of its later stages, enlarged ten diameters. 

 37. Zoea of the common crab. < 'nm-ir irroralus. (p. 530 ;) in the last stage ju 



before it changes to the megalops condition; lateral view, enlargi 



seventeen diameters. 

 38. Megalops stage of the same, just after the change from the zoea cone 



tion ; dorsal view, enlarged thirteen diameters. 



(All the figures were drawn l>y J. IT. Emerton.) 



