130 Rhodora [JULY 
On June 23d, 1918, another visit was made to this series of steep 
slopes. The outcrops and slopes were carefully scanned for Trisetum 
spicatum from the tracks without success until the place of the original 
collection was reached. Here the plant was found rather evenly 
distributed and quite abundant about the open outcrops of the rather 
short, steep part of the slope close to the tracks for perhaps the dis- 
tance of a city block and between two moist springy places about the 
outcrops. The soil in which it grew was moist but that was because 
of the recent rain for the soil on the shelves where some grew was 
shallow and suggested normally dry soil. Some however did grow 
in the springy places or at least close to where moisture is the rule. 
It grew mostly on tiny shelves of the outcrops which are lower and 
less clifflike than some others of the series here and when growing 
on the tiny shelves but a few inches wide, or less in some cases, pre- 
sented rather a striking appearance where it grew upright against 
the vertical face of the outcrop. Later in the season, on August 18, 
1918, the entire distance of about five miles between Treichler and 
Slatington was covered and the outcrops viewed from the tracks but 
the grass was seen nowhere on them excepting at the original station. 
Though found only within a limited area the plant is certainly well 
distributed and is apparently quite indigenous. It is hardly possible 
to say whether or not it grows or has grown on original outcrops. 
Some certainly: now grows on outcrops close to the marks of the drills 
used in blasting out the railroad roadway many years ago but there 
are many original outcrops on these slopes, some of them adjacent to 
the tracks, that appear to have been little if at all disturbed. Often 
these outcrops adjacent to the railroad are so well occupied by a 
generally well balanced association of native plants that it may 
easily become a matter of speculation as to what may or may not have 
been original outcrops. Tiarella cordifolia has been collected as close 
to the tracks as the Trisetum surely no more than the distance of a 
city block or two away, and there are found on the slopes close by, 
as well as on those of the whole series between Slatington and Treichler, 
such species as Acer pennsylvanicum, Acer spicatum, Cornus rugosa, 
. Ilex monticola, Lonicera canadensis and Prunus pennsylvanica —- all 
of which are more normally a strong element in the association found 
in the higher mountains northward. Sambucus racemosa and Cinna 
latifolia are found on the next series of cliffs and steep slopes about a 
mile and a half further down the river and still other species might 
