THE LADY FERN AND ITS KIN. 187 



Fertile and sterile fronds are much .alike and the 

 former are sharply distinguished from those of other spe- 

 cies by their regular rows of clear-cut sori. Beginning 

 at the base of each pinnule, these alternate on each side 

 of the midvein almost to the tip. They are usually set 

 close together and curve slightly outward at an 

 oblique angle nearly to the edge of the pinnule in a very 

 pleasing pattern. Occasionally the lower sori are double, 

 opening away from each other, and on the long slender 

 tip of the pinnae they are nearly always so. In heavily 

 fruited fronds the fruit covers nearly all the under surface 

 of the blade. The indusia are rather thick and for most 

 of the summer retain the silvery white colour of their 

 youth thus giving the common name to the plant. The 



fronds do not survive the frosts. 



i 



This species is found from Canada and Minnesota to 

 Alabama. It also occurs in Eastern Asia. It is con- 

 sidered a fairly common species never so common as 

 the lady fern, perhaps, although often forming dense 

 thickets in small areas. After studying it for many 

 years, I am inclined to agree with the author of " How 

 to Know the Ferns " that " although it cannot be classed 

 among the rare things, it is absent from many promising 

 localities." American authors frequently give this species 

 the name of Asplenium acrostichoides. This is the older 

 by three years, but has never been commonly accepted. 



The Narrow- Leaved Spleenwort. 



The rarest of the larger Aspleniums is without doubt 

 the narrow-leaved spleenwort (Asplenium angustifolium). 

 According to Eaton, it has no very near relatives any 

 where. It is a true Asplenium and not an Athyriunt 



