NOTES ON NUMERICAL VARIATION IN THE DAISY 
C. H. DANFORTH 
Numerous observers, both in this country and in Germany, have 
given attention to numerical variations in the ray florets of the Com- 
positae. For the investigation of the subject the common daisy, 
perhaps, has been most frequently used. The usual method of 
study has been simply to count and tabulate the ray florets for a 
number of heads collected from some 
prescribed locality. The results of 
such observations seem to show that 
the number of ray florets in the daisy 
is subject to a considerable amount of 
Variation ; but when a frequency curve 
ls plotted, more or less definite modes 
become evident, one on the 21-ray line 
being especially prominent. 
With a view to getting more data, I 
€xamined 4000 heads during the sum- 
mer of 1905, from which I obtained 
Tesults that agree in general with 
those previously obtained by Tower, 
and by Pearson and YULE from a 
much smaller number of heads, except 
that their data do not demonstrate the 
Presence of a mode on 34, as do my own 
observations and those of Lupwic (3). 
a the investigation in question I col- 
ected 1300 heads from the vicinity of 
Tufts College, Medford, Mass.; as 
“sal more from Norway, Oxford 
: y, Maine; and 1400 from Dennis, 
ape Cod, Mass. In these lots 12 was 
TABLE I 
DISTRIBUTION OF RAYS FOR 4000 
ADS COLLECTED AT MED- 
FORD, NORWAY, AND DENNIS 
Rays Heads 
12 I 
13 9 
14 + 
15 9 
16 iz 
17 I2 
18 25 
19 49 
20 135 
21 423 
22 37° 
23 205 
24 278 
25 216 
26 ect 
27 176 
28 ror 
29 192 
30 184 
sr 224 
32 218 
: 3 266 
34 393 
35 — 
36 47 
37 of 
38 9 
39 3 
40 3 
the lowest number of rays found in any one head and 4o was the 
349] 
highest. The total number of rays produced by the whole lot was 
[ 
Botanical Gazette, vol. 46 
