Frrn Fiora oF NORTHEASTERN IOWA 101 
tops of large detached boulders at the bottom of deep, 
shaded ravines. 
ASPLENIUM ANGUSTIFOLIUM Michx. (Asplenium pyc- 
nocarpon Spreng.) Allamakee County; in rich shaded 
wood soil on slopes and at the foot of timbered bluffs 
at Waukon Junction and at Lansing, Iowa; infrequent 
or rare; seemingly preferring the blufis near the Mississ- 
ippi River. I have also a specimen from Jackson 
County. 
ASPLENIUM FILIX-FOEMINA (L.) Bernh. (Athyrium 
filix-foemina (L.) Roth). Winneshiek, Allamakee, Clay- 
ton, and Dubuque Counties. Woods and thickets, the 
most abundant fern and very common throughout this 
region, as well as all the portions of the State. 
ASPLENIUM ACROSTICHOIDES Sw. (Asplenium thelyp- 
teroides Michx. Athyrium thelypteroides (Michx.) Desv.) 
Allamakee and Dubuque Counties. Mr. Orr writes: 
“Two small colonies near Waukon, one at Lansing, 
probably rare in-the county.” 
ADIANTUM PEpATuM IL. Winneshiek, Allamakee, 
Clayton, and Dubuque Counties; rich woods; common. 
Preris aquitina L. (Pleridium aquilinum (L.) 
Kuhn.) Winneshiek, Allamakee, Clayton, and Du- 
buque Counties; quite common. The habitat is medium 
ry or moist soil along hillsides covered with thickets 
or woods. 
PELLAEA ATROPURPUREA (L.) Link. Winneshiek, 
Allamakee, Clayton, and Dubuque Counties. Found 
also in the neighboring counties of Fayette and Dela- 
Ware. This species prefers limestone cliffs, but grows 
on sandstone. Mr. Orr notes: “Abundant throughout 
Allamakee County on all limestone rocks. Shows most 
luxuriantly where rocks are moist and shaded. Grows 
abundantly in rock cuts of C. M. & St. P. R. R. west 
of McGregor. I have seen fine specimens near Harpers 
Ferry, Iowa.” 
