FERN FAMILY 103 



NARROW-LEAVED SPLEENWORT. 



Aspleniiim angustifolium. 



Frond simply pinnate ; pinna; from three to 

 four inches long, stalked, alternate, entire or 

 minutely toothed, tapering to a point. 



This fern is found in rich, moist woods only 

 occasionally. It is sometimes known as Swamp 

 Spleenwort. The fronds are unusually delicate, 

 pale green and smooth, growing from one to two 

 feet high, in tufts. 



The fertile fronds are few, in the middle 

 of the cluster, taller and with longer stipes 

 than the sterile, and with narrower, shorter 

 pinnae. 



The fruit-dots are linear, in rows of from 

 twenty to forty, diverging from the midvein, 

 and parallel with the veins. They at length be- 

 come confluent and conceal the slightly convex 

 indusia ; time of maturity, September. 



SILVERY SPLEBN"WORT. 



Asplenium tlielypteroides {A. acrostichoides). 

 Frond pinnate; pinnae from three to five 

 inches long, deeply cut into blunt, obscurely 

 toothed segments. The stipe is slightly chaffy. 

 The fronds are grouped together, although not 

 growing exactly in crowns. They are very thin 

 and delicate in texture for such large ferns. We 



