360 SEMI-CENTENNIAL OF TORREY BOTANICAL CLUB 
improved large-leaved, improved white-leaved, and improved 
spotted, when treated this way come into heavy bloom and die as 
annuals. The plants of the Treviso strain have therefore been 
studied in only one year of bloom. 
The preliminary studies of 1912 indicated that usually there is 
such a marked decrease in flower number per head as the season 
advances that data which are to be considered adequate should 
be taken during the entire flowering season, Hence, in the col- 
lection of data here reported, the method has been to begin on 
the first day of blooming and to continue throughout the season, 
obtaining counts of ten heads per plant, when that number was 
in bloom, on each of at least ten different dates per month at 
intervals of every third day, or as close to that schedule as con- 
ditions allowed. The flower heads counted were taken at random 
from various branches on the plant and from various parts of the 
different branches. The heads selected were usually removed, 
the flowers counted, and the number recorded on sheets specially 
ruled and tabulated for dates and numbers. In 1913 and 1914, 
many data were also taken on the character of each flower as to 
whether ligulate or tubular, as to number of teeth in the ligule and 
the depth of lobing. In 1915 and 1916 data were secured for 
flower number only. Special methods were used to obtain certain 
data; for all plants studied in I9I5 data were taken every day 
during the first twenty days of blooming; and on five plants data 
were taken on all flower heads (excepting those that opened on 
Sundays or on days of heavy rainfall) with reference to their 
position on the various branches of the plant; this was done to 
determine more exactly the relation of position to time of blooming 
and to the intraseasonal change in number, both of which appear 
in the data as more generally collected. Data have been collected 
from a few individual plants during four successive years of growth, 
but the greater number of plants have been studied in the first of 
bloom. 
Considering all plants of all stock, in 1913 data were collected 
from 63 plants, in 1914 from 110, in I9I5 from 351, and in 1916 
from 450. The total number of individual plants involved is 832. 
he number of heads counted approximates 5,500 in 1913, 20,000 
in 1914, 113,000 in 1915 (including here data collected every day 
