.KEY TO THE GENERA. 



The most prominent characteristics are italicised. 



SECTION I. 



(Sporangia in spikes, panicles or berry-like structures.) 



* FRUITING FRONDS WHOLLY FERTILE. 



PAGE. 



1 Fruit in a one-sided spike ; plants very 

 small ; sterile frond thread like. 

 Curly grass. 



SCHIZJEA. 277 



Schizaea 



1. Fruit in a club-shaped, thrice pin- 

 nate, woolly, brown spike ; fronds 

 bipinnatirld ; fruit in early spring. 

 Flowering fern. 



OSMUNDA. 



J. Fruit in berry-like green structures, 

 in a twice pinnate spike ; fronds 

 broad and coarse ; rootstock creep- 

 ing. Fruit in late summer. Sen- 

 sitive fern. 



ONOCLEA. 



253 



Struthioptcri* 



Fruit in nearly cylindrical slightly 

 notched pinnae; fertile frond pin- 

 nate ; sterile tall, bipinnatifid ; 

 rootstock erect, fruit late. Ostrich 

 f em . STRUTHIOPTERIS. 257 



