Bancroft.—On the Xylem Elements of the Pteridophyta. 759 
Fig. 8. Selaginella Wildenovii. Longitudinal section corresponding to the transverse section 
shown in the previous figure. 
Fig. 9. Psilotum triquetrum. Transverse section of xylem of aerial stem—the middle lamella 
traverses spaces between the elements. 
Fig. 10. Psilotwn triquetrum. Longitudinal sections, showing the narrow connexions between 
the lignified layers. 
Fig. 11. Lygodium scandens. Transverse section of xylem of twining petiole. Compare the 
wide splits exhibited by this part of the xylem with those in 
Fig. 12. L. dichotomum (petiole), where they are relatively much narrower. 
Fig. 13. L. dichotomum. Longitudinal section, corresponding to Fig. 12. 
Fig. 14. Tmesipteris tannensis. Transverse section of xylem of aerial stem. The lamella is 
seen in the spaces between the tracheides. 
Fig. 15. Tmesipteris tannensis. Longitudinal section, showing the connexions between the 
thickening bars. 
Fig. 16. Aneimia fraxinifolia. Transverse section of xylem of petiole. No spaces are shown. 
Cf. Marattia fraxinea. 
Fig. 17. Aneimia fraxinifolia. Longitudinal section, corresponding to Fig. 16. 
