64 W. K. BROOKS AND E. B. WILSON. 



FIGURE 4. Basal joints of the maxillipeds of the larva shown in Plate 

 VI, Figure I. From a drawing by W. Brooks. 

 a, base of first maxilliped; b, base of second maxilli- 

 ped ; c, third maxilliped; d, first pereiopod; e, edge 

 of carapace. 



FIGURE 5. Mandible of the zoea shown in Plate YI, Figure 5. From 

 a drawing by E. B. Wilson. 



FIGURE 6. First and second maxillipeds of the zoea shown in Plate 

 VI, Figure 5. From a drawing by W. K. Brooks. 



FIGURE 7. Mandible and maxilla of the larva shown in Plate VI, 

 Figure 1. From a drawing by W. K. Brooks. 

 M, mandible ; MX, first maxilla ; MX', second maxilla. 



FIGURE 8. Side view of the zoea, one day after moulting the embryo- 

 nic skin. From a drawing by E. B. Wilson. 



ERRATA. 



Page 60. bottom line, 

 for " external," read "internal." 

 for "internal," read "external." 



