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 asa sort 
of stubble still attached to the rootstock. 
Thissingle characteristic may be depended 
upon to distinguish the species from  RoorsTock, 
Cheilanthes vestita, a fern which other- 
wise very much resembles it, evenas 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 pinne 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 Ilvensts 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 Kefttucky 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, 
