112 ASPIDIUM 



SPINULOSE SHIELD FERN: 



Aspidium spinuldsum. 

 (Nephrodiumj Dryopteris spinulosa.) 



Fronds 1 to 3 feet high^ finely cut with a deli- 

 cate, lace-like effect, twice pinnate; pinnae ob- 

 lique to the rachis, elongated-triangular, the lowest 

 pairs broadly triangular; pinnules set obliquely to 

 the midribs, with spiny-toothed lobes, those on the 

 lower side usually elongated especially in the low- 

 est pinnae; scales on the stipes pale brown. 



Fruit dots borne on the backs of the ordinary 

 fronds; indusium smooth, without marginal glands. 



Found in rich woods from Virginia and Ken- 

 tucky to the far north. 



In the variety intermedium the margin of the 

 indusium is irregular and beset with minute, 

 stalked glands, and the scales on the stipe are 

 brown with a darker center; common. 



In the variety dilatatum the fronds are long egg- 

 shaped in outline, the lower pinnules often much 

 elongated, the indusium smooth without marginal 

 glands, and the scales on the stipe have dark cen- 

 ters. Found chiefly in rocky, upland woods. 



NOTES. 



