Explanation of Plate I. 



Hymenofhyllum polyanthos Swz. p. 127. 

 Fig. 1. A sterile frond, with rootstock. X 1. 



Trichomanes membranaceum L. p. 129. 

 Fig. 2. A sterile frond, showing marginal scales. X I. 

 Fig. 3. A lobed fertile frond. X i- 



Trichomanes punctatum Poir. p. 129. 

 Figs. 4-7. Fertile fronds, showing variation in division and in the 



length of the stipe. X J- 

 Fig. 8. A sessile sterile frond. The marginal hairs are not shown. X 1. 

 Figs. 9-12. Pieces of rootstocks with fronds, showing variation in form, 

 size and division of the fronds, and in the length of the stipes. X i* 

 Fig. 13. A stellate marginal hair. Magnified. 

 Fig. 14. A single involucre. Magnified. 



