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following year, which difference probably depends on the different latitudes 
in which the observations are made, If the Vermont dates are correct, 
which fact I have no reason to doubt, P. comnmme and P. juniperinum in this 
region require fifteen to sixteen months for the development of their sporo- 
phytes. 
The interest in the phaenological relations of mosses, of which the note 
in The Bryologist bears evidence, encourages me to renew in a modified 
form a proposal of phaenological observations on mosses that I made in 1878, 
in the' 1 Revue Bryologique,” which proposal, however, has hitherto led to 
no results. In phanerogams the phaenological observations are, as is well 
known, always continued through as long a period of years as possible in 
order to get fully comparable medium dates in which the variations of sin- 
gle years are eliminated. Desirable as such medium dates may be in 
mosses, I do not, however, dare to insist upon the carrying on of observa- 
tions through a period of years in each place, because most bryologists will 
shrink from undertaking so toilsome a task. Dates from even a single year 
will be of great value and will open the possibility of interesting comparisons 
of the phaenological differences of mosses in different regions. 
As it is the beginning of the blooming and the fructification that have 
been made the object of phaenological observations in phanerogams, I pro- 
pose that the same phenomena be observed also in mosses. The beginning 
of the blooming in mosses is to be considered to occur when one or two 
archegonia only, in at least two flowers of a species, are opened, while the 
other archegonia are still closed and uncolored, or, if archegonia are not 
accessible, when only one or two antheridia in at least two flowers are 
opened and uncolored or brown, while all the other antheridia are still 
closed. In determining the blooming time however, if archegonia are at hand, 
these ought in the first place to be consulted, because we are less subjected 
to errors when determining the blooming time of a moss by the archegonia 
than when judging by the antheridia. Especially I warn observers against 
believing the blooming to have begun in a moss merely because its anther- 
idia appear fully developed, if at the same time no antheridium is opened, as 
antheridia may often appear fully developed many months before they open 
and their antherozoides begin to swarm. In getting the date of the first 
blooming of a moss I have found it the least labor to collect specimens of the 
species that I desire to examine at different times of the year, for instance 
every fortnight, and then afterwards to examine all the collected specimens 
at once. 
The fructification is according to my proposal considered to have begun 
when in a species about five to ten lids are naturally detached from their 
fruits; in dried specimens the lids are, as every bryologists knows, detached 
earlier than in nature, on which account dried specimens are less adapted 
for these researches. 
My proposal was limited to only a small number of species. In making 
the choice of species I tried to get mosses that have a wide distribution, are 
easily recognized, have a limited season of blooming and fruiting and, as far 
