STRUTHIOPTERIS. 135 



GENUS V. 



STRUTHIOPTERIS. 



Having fronds of two kinds, the barren ones large and bold 

 and the fertile much smaller, with contracted resolute margins, 

 forming as it were a universal indusium. 



Veins pinnate and free. 



Spore cases lateral; the base of the pedicels concrete, and 

 producing an elevated thickened receptacle. 



The habit of the genus exceedingly beautiful, and very 

 distinct. 



Most authorities consider that there are two species, one 

 from Germany and the other a native of North America, yet 

 they are scarcely distinguishable; probably the geographical 

 separation of the two plants has had more to do with placing 

 them as distinct species, thaa any specific difierence in the plants 

 themselves. 



VOL. II. 



