202 EXPLANATION OF THE PLATES. 



Fig. 



21. Labial palpi of Formica exsecta, worker. 



22. Antennae of Formica fusca, male. 



23. cunicularia, male. 



24. Abdomen of Formica virescens, male, 



25. Antennae of Formica virescens, male. 



26. Scale of the petiole of Formica virescens, female. 



27. Lateral view of the scale of Formica virescens, female. 



28. Head of an Ant, showing the position of the frontal area 



at a. 



29. Head of an Ant, with the frontal area obsolete at A. 



30. Formica gigas, worker major, natural size. 



PLATE IV. 



1. Anterior wing of Polyergus rufescens, female. 



2. Head of Polyergus rufescens, male. 



3. Scale of the petiole of Polyergus rufescens, male. 



4. Head of Polyergus rufescens, female. 



5. Antennae of Polyergus rufescens, female. 



6. Labial palpi of Polyergus rufescens, female. 



7. Maxillary palpi of Polyergus rufescens, female. 



8. Scale of the petiole of Polyergus rufescens, female. 



9. Mandible of Polyergus rufescens, worker. 



10. Labial palpi of Polyrhachis. 



11. Maxillary palpi of Polyrhachis. 



12. Thorax of Polyrhachis mutatus, worker. 



13. Scale of the petiole of Polyrhachis mutatus, worker. 



14. Gagates, worker. 



15. hastatus, worker. 



16. Thorax of Polyrhachis hastatus, worker. 



17. Scale of the petiole of Polyrhachis aciculatus, worker. 



18. Thorax of Polyrhachis aciculatus, worker. 



19. bihamatus, worker. 



20. Thorax and abdomen of Polyrhachis furcatus, worker. 



21. Scale of the petiole of Polyrhachis laboriosus, worker. 



22. worker : lateral view. 



23. constructor, worker. 



24. piliventris, worker. 



25. inermis, worker. 



26. Thorax of Polyrhachis inermis, worker. 



27. Scale of the petiole of Polyrhachis defensus, worker. 



28. Lateral view of the scale of Polyrhachis rufipes, worker. 



29. Scale of the petiole of Polyrhachis tyrannicus, worker. 



30. Lateral view of the thorax and abdomen of Polyrhachis con- 



similis, worker. 



