32 GLEASON: SOME APPLICATIONS OF THE QUADRAT METHOD 
This method, while doubtless better than the original one, is 
still deficient in allowing equal weight to such small slender plants 
as Erigeron canadensis and large bushy ones as Gaylussacia 
baccata. If each plant could be further weighted by a multiplier 
expressive of its size, a better index would doubtless be attained. 
In this particular case, for example, each plant of the latter species 
occupies probably 400 times as much ground space as the former. 
So far no serious attempt has been made to follow out this sug- 
gestion. 
It is freely admitted that the expression ‘‘ FI 55’’ means little 
to a person who has not already experienced its meaning by actual 
field work. But to such persons it does present at once an idea of 
the relative abundance of that particular species, and an idea 
much more accurate than any such general expression as common, 
rare, or copious. Students who have used the method adopt it 
into their scientific vocabulary and actually use it in their con- 
versation, almost as freely as they refer to degrees of temperature. 
The writer has heard a student, describing the luxuriant growth of 
Epilobium angustifolium following a recent fire, state that it must 
have had ‘“‘a frequency index at least 90,”’ instead of resorting to 
the usual hyperbole to express great abundance, or, in alluding to 
a new station for a Habenaria, say ‘‘There was a good deal of it 
all through the woods: FI probably 5 or 10.” And if such a 
student should read an account of an utterly unfamiliar vegetation 
in some remote part of the world, in which the frequency indices 
were given, he would at once have a relatively clear idea of the 
actual conditions. 
Nevertheless, the quantitative study and description of vege- 
tation are still in their infancy, and there is every opportunity 
for great improvement. 
NEw York Botanica GARDEN 
LITERATURE CITED 
Clements, F.E. 1904. The development and structure of vegetation. 
Rep. Bot. Surv. Nebraska 7. 
——- 1905. Research methods in ecology. Lincoln. 
Drude, O. 1890. Handbuch der Pflanzengeographie. Stuttgart. 
Fernald, M. L. 1919. Lithological factors limiting the ranges of 
Pinus Banksiana and Thuja occidentalis. Rhodora 21: 41-67. rf. 
