Explanation of Plate X. 



Adiantum pulverulent tun L. p. 148. 

 Fig. 1. The basal half of a pinna. X i« 



Adiantum concinnum H. B. K. p. 149. 

 Figs. 2-7. Segments of various sizes and forms. X 1. 



Adiantum tenerum Svvz. p. 149. 

 Figs. 8, 9. Fertile segments. X i- 

 Fig. 10. A sterile segment. X 1. 



Adiantum dolosum var. ivilsoni (Hook.) Bak. p. 149. 

 Fig. 11. A fertile pinna. X 1. 

 Fig. 12. A young, sterile, simple frond. X f. 



Dictyoxiphium panamense Hook. p. 150. 

 Fig. 13. A scale from the stipe. Magnified. 

 Fig. 14. A part of sterile frond, showing venation. X 1. 

 Fig. 15. A part of fertile frond, showing venation, fruit, and the inner 



involucre. Magnified. 

 Fig. 16. A part of fertile frond, showing interrupted sori. X I. 



