432 SEMI-CENTENNIAL OF TORREY BOTANICAL CLUB 
The frequency distribution is given for classes of 0.010 extent. 
Here, as for values of flower number for the first day of bloom (a) 
the lines show some noticeable characteristic differences; for line 
descending from the F; plant (A X Ex) no. 4 the — values were 
most in evidence. In the other two lines a considerable number 
of plants exhibited + values. The heredity of the type of seasonal 
change is in general indicated by line performances. In respect 
to immediate parentage, the agreement is less close than for values 
of flower number. There has been no attempt rigidly to select 
for various values of rate of change. That the performance is 
more sporadic for rate of change than for flower number will be 
further indicated in the study of various races. 
2. DETAILED ANALYSIS OF SIX RACES AS TO INHERITANCE OF 
FLOWER NUMBER PER HEAD 
In the F; and F, generations of the family with the original 
parentage wild white-flowered (A) x Barbe de Capucin (Е), 
it became evident that the pedigreed breeding in lines had resulted 
in the development of several types, races, or elementary species 
which differed from each other most decidedly in habit of growth. 
This gave opportunity for the study of the flower number in rather 
widely diverse races. Comparisons can be made with reference 
to the relation of various habits of growth to performance in 
flower production. The detailed records of lines of parentage 
also give opportunity for further analysis of the influence of selec- 
tion and the degree to which heredity is in evidence. 
A. The history and characteristics of a semi-dwarf, sparsely 
branched race (race 1, or line (A X Ex) —4-3—). In mature 
development for the first year of growth this race was character- 
ized by low stature (1 1/2 to 2 1/2 feet tall) and by a sparse and 
coarse branching habit. The branches were very brittle, and 
there was a very general death of the branches due to suscepti- 
bility to a bacterial or fungous disease. The death of the tips of 
the branches added considerably to the dwarf-like appearance and 
decreased the total number of flower heads that came to bloom. 
Twelve plants of the F; and thirty-one plants of the F, of this race 
were quite uniform in the general vegetative habit of growth. 
In the rosette stages, however, the plants which later made smallest 
