106 
Miscellanea 
III. Variation in Flower-heads of Gaillardia Aristata. 
By W. W. bobbins. 
This conspicuous Composite has flower-heads about 6 cm. broad with purplish-brown centi-es 
and bright orange rays. In some heads a part of the rays are of the usual length and colour 
but tubular {Torreya, vi. 190, 1906) as was noted by the writer in a previous paper. During 
the summer of 1907 from July 17 to August 14 a collection of 500 flower-heads was made 
from localities in the neighbourhood of Boulder. 
Gaillardia aristata commonly grows in loose soil where there is not much water. About 
one-half of the flower-heads studied were, however, collected at an altitude of 9000 feet, from 
plants growing in an aspen grove. These plants were well-developed and the rays larger than 
those in plants found growing in the open. Other than this no special variation has been 
noted in the rays of plants growing in different altitudes and habitats. 
Records were made of the number and character of all the ray-flowers in each head studied. 
A part of the data appear in the following table. 
1 
2 
S 
k 
i 
5 
6 
7 
8 
Number of 
rays in a 
bead 
Number of 
lieads 
Number of 
heads with 
all the lays 
ligulate 
Number of 
heads with 
all the rays 
tubular 
Number of 
heads with 
mixed ligu- 
late and 
tubular rays 
Percentage 
of heads 
with all the 
rays ligu- 
late 
Percentage 
of heads 
with all 
the rays 
tubular 
Percentage 
of heads 
with mixed 
hgulate and 
tubular rays 
9 
10 
11 
12 
13 
U 
15 
16 
17 
18 
19 
20 
21 
22 
23 
2k 
25 
26 
27 
28 
33 
1 
8 
23 
33 
123 
53 
47 
55 
45 
33 
21 
21 
8 
13 
5 
4 
1 
•2 
0 
3 
1 
1 
5 
16 
27 
95 
40 
31 
41 
33 
21 
14 
10 
7 
6 
2 
1 
0 
0 
0 
0 
0 
0 
0 
0 
0 
1 
1 
1 
1 
0 
0 
1 
0 
0 
1 
0 
0 
0 
0 
0 
0 
0 
0 
3 
7 
6 
27 
12 
15 
13 
12 
12 
6 
11 
1 
6 
3 
3 
1 
2 
0 
3 
1 
100 
62 
69 
81 
77-2 
75-4 
65- 9 
74-5 
73 
63 
66- 6 
47 
87 
46-1 
40 
25 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0- 9 
2 
2-2 
1- 9 
0 
0 
4 '9 
0 
0 
6-8 
0 
0 
0 
0 
0 
0 
0 
0 
38 
31 
19 
21- 9 
22- 6 
31-9 
23- 6 
27 
37 
28-5 
53 
13 
46-1 
60 
75 
100 
100 
0 
100 
100 
500 
350 
6 
144 
70 
1-2 
28-8 
To illustrate what the table shows the 13-rayed head may be taken as an example. Columns 
1 and 2 show that of the 500 heads examined 123 had 13 rays in a head. Column 3 shows that 
95 of these had all ligulate rays ; Column 4 shows that 1 had all tubular rays; Column 5 shows 
