1916] Biology of Aquatic Lepidopter a 187 



EXPLANATION OF PLATES. 



Plate VII. 



Nymphula maculalis. 



Dorsal view of recently hatched larva. 



Dorsal view of larva in the second instar. 



Dorsal view of larva in the third instar. 



Egg as it appears immediately before hatching. 



Egg masses on lower surface of leaf of Nymplicea americana. p, puncture 



through leaf made by female Donacia; d, eggs of Donacia sp. ; n, eggs of 



Nymphula maculalis. 



Plate VIII. 

 Fig. 6. Ventral view of pupa. 

 Fig. 7. Lateral view of pupa. 

 Figs. 8-10. Ventral view of terminal segments of pupa, showing some common 



forms of variation in number and arrangement of carina. 

 Fig. 11. Dorsal view of larva of Nymphula icciusalis. 



Plate IX. 

 Figs. 12-19. Leaves of Nymphcea americana showing characteristic work of larvas 

 of Nymphula maculalis. Figs. 12, 13, 14 and 17 show extent to which 

 surface of food plant may be reduced. In Figs. 13, 16 and 19, the small 

 marginal incisions are the work of young larvae. In Figs. 12, 14 and 

 17, the broad marginal incisions were produced by full-grown larvae. 



