ILLUSTRATIONS. 



Page. 



Fig. 1. Xylococcus betulce: work on birch tree 14 



2. Xylococcus betulce: larvae, male and female 20 



3. Xylococcus betulce: end of body of female - 21 



4. Xylococcus betulce: end of body of female, second stage 21 



5. Xylococcus betulce: end of body of female, third and fourth stages 22 



6. Xylococcus betulce: stages of female 22 



7. Xylococcus betulce: adult female 23 



8. Xylococcus betulce: parts of male 25 



9. Lecanium nigrofasciatum: adult female 27 



10. Lecanium nigrofasciatum: antenna and leg 28 



11. Elaphidion villosum: larva, beetle, pupa, etc 36 



12. Elaphidion inerme, enlarged 41 



13. Work of Elaphidion subpubescens 41 



14. Elaphidion mucronatum, enlarged 43 



15. Work of Agrilus anxius on birch limb 46 



16. Work of Agrilus anxius on birch trunk _ . . _ . 47 



17. Agrilus anxius: larva, pupa and adult 45 



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