158 
Psyche 
[October 
FLOWER VISITS OF INSECTS 
By Charles Robertson 
Carlinville, Illinois. 
In the study of the pollination of flowers by insects (6) a 
good many observations have been made which relate primarily 
to the habits of insects and only indirectly, if at all, to the elucida- 
tion of insect flowers. It is proposed here to consider the data 
from the standpoint of the insects. 
The flower groups adopted are divided into a social set, 
whose flowers are in heads, spikes or close umbels, so that insects 
pass from one to another without taking wing or climbing, and 
a non-social set. The latter contains 54.4 per cent of the flowers, 
and is divided into Ma, long-tongued bee flowers, including 11 
adapted to birds, hawk-moths and butterflies, and Mi, short- 
tongued bee flowers, including six fly flowers. The social set 
includes Mas, long-tongued bee flowers; Mis, short-tongued bee 
flowers; and Pol, visited by miscellaneous short-tongued insects. 
The insect visits were first distributed under Muller’s 
flower classes. These were then divided into non-social and social 
sets and the visits were distributed again under them. Of 9 
cases, maxima under Hb fell under non-social Hb in 6. In 27 
other cases, however, maxima under B, AB, or A always fell 
under the social sets. 
The percentages for each class and color and the visits ob- 
served are: 
Non-social 
Social 
Total 
Colors 
Ma 
Mi 
Mas 
Mis 
Pol 
Red 
White 
Yellow 
I.ocal Flora 
28.3 
27.9 
16.4 
22.0 
5.1 
540 
29.2 
39.6 
31.1 
Flowers observed 
30.2 
24.2 
18.7 
21.5 
5.2 
437 
30.2 
39.1 
30.6 
Before July 
28.9 
32.3 
11 .0 
22.9 
4.6 
235 
26.3 
44.6 
28.9 
After June 
30.5 
15.2 
28.2 
19.0 
6.8 
262 
34.3 
33.5 
32.0 
Pollinating visits 
7.5 
13.3 
20.4 
39.8 
18.7 
13971 
16.8 
51.3 
31.7 
Non-pollinating visits 
41.1 
9.5 
31.3 
10.9 
7.0 
852 
46.3 
33.3 
20.3 
