EXPLANATION OF PLATE VIII. 



FIGURE 36. Squilla empusa Say, (p. 536;) lateral view of the free-swimming larvao 

 in one of its later stages, enlarged ten diameters. 



37. Zoea of the common crab, Cancer irroratus, (p. 530 ;) in the last stage just 

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

 seventeen diameters. 



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

 tion ; dorsal view, enlarged thirteen diameters. 



(All the figures were drawn by J. H. Eraerton.) 



