. 
1920] Second Report on Floral Areas 83 
These species seem, for the most part, to be distributed very evenly, 
although somewhat dependent on suitable habitats. Cystopteris 
fragilis, for instance, a plant of shaded rocks or rarely of woodland 
soil, is not known from Cape Cod, where such conditions are lacking. 
Dennstaedtia punctilobula, Thelypteris marginalis, T. palustris and 
T. spinulosa are apparently less common in northern Maine than else- 
where. "Through them, the ranges grade off into those of the follow- 
. ing division. 
SeEcrES or Ricu Sorrs. 
Adiantum pedatum Polystichum acrostichoides 
Athyrium acrostichoides Pteretis nodulosa 
These ferns are abundant in rich soils, but avoid the spruce forest 
and sandy regions. The first three are woodland species, the Poly- 
stichum frequenting drier situations than the others. Pteretis nodulosa 
is by preference a plant of the richest alluvium, where it grows five 
or six feet tall. It grows also in moist upland country, especially 
where there is a trace of lime in the soil. Like the other species of 
this division, it avoids northwestern and extreme northern Maine 
and the coastal plain areas of Cape Cod; it also avoids the outer Maine 
coast east of the Kennebec and all of southeastern Massachusetts, 
and is rare in eastern Connectieut and Rhode Island (two stations, 
one now eradicated). 
NORTHERN SPECIES. 
A B 
Thelypteris Dryopteris Athyrium angustum, var. laurentianum 
S Phegopteris Polystichum Braunii 
Woodsia ilvensis Thelypteris spinulosa, var. americana 
The species of group A are northern types of wide range in New 
England and perhaps as well placed with the generally distributed 
species, but, unlike them, becoming notably less frequent in southern 
New England. Thelypteris Dryopteris, common northward, is rare 
in eastern Massachusetts and eastern Connecticut and is not reported 
from Cape Cod nor the southern islands. It has two Rhode Island 
stations, both in or near Providence, but is known to have been in- 
troduced at one of them; and the other is under suspicion. T. 
Phegopteris has a similar range, but is more frequent southward, 
has four stations in Rhode Island, and has been found during the past 
