PLATE XXVI. 

 ARCTOCORIXA ALTERNATA. — Kansas Material. 



Fig. 1. Egg of the Corixid species here considered. 



Fig. 2. Adult Corixid, Arctocorixa alternata. 



Fig 3. Egg of a smaller species. 



Fig. 4. First instar nymph. 



Fig. 5. Second instar nymph. 



Fig. 6. Tarsus and claws of hind leg of first instar. 



Fig. 7. Third instar. Note the fringe of black hairs on the wing-pads. 



Fig. 8. Egg shell after hatching, showing the characteristic rupturing 

 of the egg for the egress of the nymph. 



Fig. 9. Fourth instar nymph. 



Fig. 10. Front leg of late fifth instar nymph, showing the tibia and 

 tarsus of the adult within the terminal nymphal segment. 



Fig. 11. Fifth instar nymph. 



Fig. 12. The foreleg of the adult male. 



Fig 13. Ventral view of abdomen of female. 



Fig. 14. Antenna of third instar nymph. 



Fig. 15. Antenna of late fifth instar, showing the three distal seg- 

 ments of the adult in the terminal nymphal segment. 



Fig. 16. Antenna of adult. 



Fig. 17. Ventral view of abdomen of male, showing the peculiar 

 arctoco asymmetry of the segments. Plate appeared in Jr. N. Y. Ento. 

 Soc, XXV. 



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