THE WOODSIAS. 95 



The stipes are comparatively short and 

 remarkable for possessing an obscure, 

 joint an inch or more above the root- 

 stock, at which point they separate when 

 the fronds die, leaving the bases as a sort 

 of stubble still attached to the rootstock. 

 Thissingle characteristic may be depended 

 upon to distinguish the species from ROOTSTOCK. 

 Cheilanthes vestita, a fern which other- 

 wise very much resembles it, even as to habitat. The 

 fronds seldom attain a length of more than eight inches 

 and the average length is several inches less. They are 

 rather stiff, long-lanceolate in outline and pinnate with 

 numerous pinnae that are themselves cut nearly to the 

 midribs into short, rounded, close-set lobes. Occasion- 

 ally the lobes nearest the rachis are distinct. 



The sori are borne on the backs of the veins on the 

 underside of ordinary fronds and near the margins, but 

 owing to the hair-like scales by which they are sur- 

 rounded are seldom very noticeable. They are round in 

 shape and have the indusium fixed underneath the 

 sorus. The indusium, however, is scarcely entitled to the 

 name except by courtesy. It consists simply of a few 

 slender hairs which curve over the sporangia in youth 

 *' as if attempting to protect what they cannot conceal." 



Woodsia Ilvensis is a northern species, being found in 

 Greenland and throughout British America as well as in 

 northern Europe and Asia. In the United States it 

 ranges to North Carolina and Kentucky and while it is 

 by no means a common species, it is abundant in certain 

 localities. It is found upon various rocks but seems to 

 have a preference for those of igneous origin. In Canada, 

 it is reported to lose its fronds at the approach of winter, 



