FRONDS OR LEAVES 



75 



FIG. 39. Filicales. Spore-bearing fronds. 1, Sori arranged along the 

 margin of the pinnules of evergreen wood-fern (Dryopteris marginalis) ; 2, 

 sori arranged in parallel rows on the back of the frond of Hart's-tongue 

 fern (Phyllitis scolopendriwri) ; 3, Christmas fern (Polystichum acrostichoides) ; 

 4, march shield fern (Dryopteris Thelypteris) . Sori completely covering the 

 back of the pinnules as in 5, lady fern (Athyrium Filix-foemina) . 



