72 FERNS : BEITISH AND FOEEIGN. 



Sub-Order IV. Osmundacea. 

 Ring apical, often rudimentary only. 



Tribe I. Schizae. Sporangia, produced on contracted racemes, 

 or on terminal or marginal spike-like appendices, ring 

 complete. 

 II. Osmundese. Sporangia globose. Ring rudimentary 



only. 

 2. Exannulatae. Sporangia coriaceous, destitute of a ring. 



ORDER II. Marattiacece. 



Fronds circinate. Sporangia dorsal, free, or connate, opaque, 

 coriaceous. 



ORDER III. Ophioglossacece. 



Vernation straight, the fronds rising from a root-stock, consisting 

 of a fascicle (more or less according to age) of fleshy roots. Sporangia 

 homogeneous, connate on spikes, or free and paniculate. 



ORDER IV. Lycopodiacece. 



Plants with indefinite prolonging, erect or pendulous, stems 

 furnished with acerose rusciform, or jungermania-like leaves (some- 

 times very small), bearing 1-3-celled sporangia in their axes, or 

 on catkin-like spikes. 



ORDER V. Marsileacece. 



Plants floating or growing in water, consisting of grass or trefoil- 

 like leaves, or branched with imbricate leaves, bearing 1-3, or 

 many-celled sporangia at their base or otherwise (see the characters 

 of the respective genera). 



