54  Pretz: FrorA oF LEHIGH COUNTY, PENNSYLVANIA 
PTERIDOPHYTA 
In the following list the writer has attempted to present, with 
particular reference to Lehigh County pteridophytes, some ob- 
servations that may be of more general interest. For the sake 
of brevity these observations have been reduced to a minimum. 
Stations have been mentioned for some of the rare or less frequent 
species and an attempt has been made to have the original dis- 
coverers of such stations receive the credit that is due them. In 
this connection it has not been thought necessary to mention more 
than the original collection from a station. 
Material from practically all of the stations mentioned is in 
the herbarium of the writer as well as, in part at least, in that of 
other collectors. The inclusion of all the data would only increase 
the list unnecessarily. The exact measurements given are from 
herbarium material almost exclusively. They are used merely 
as a guide in connection with average or luxuriant growth. The 
figures in parenthesis following the length of leaf indicate length 
of stipe + length of blade. Herbaceous and evergreen are not © 
to be taken too literally but serve to indicate comparative hardi- 
ness of the species. Itis well known that sterile fronds in general 
outlast the fertile and it has not been thought necessary to indi- 
cate in every case the part protection plays in the apparent hardi- 
ness of a species. Seasons vary too with the years. 
In general the pteridophytes of the county follow in relative 
frequency and abundance certain broad lines due to the distribu- 
tion of habitats favorable to their growth. The term “the South 
Mountains” used in this connection is general and includes all 
of the hills of this range but refers particularly to the main ridge 
of these hills, about three miles southward from Allentown, called 
Lehigh Mountain, On some of the spurs and outlying hills of 
this range some species, like the spinulose wood ferns, become rela- 
tively less abundant, especially to the south within the county. 
ADIANTUM PEDATUM L. 
General in moist situations, growing on all formations and soils, 
but most abundant in boggy areas sand along streams | on the South 
No OTE: iNiese the éollectan’ s name is aot given the specimens were pollebted 1 rath 
the writer 
