FLOWERS AND INSECTS. XXI 
DATA OF ANTHECOLOGY 
CHARLES ROBERTSON 
In Knutn’s Bliitenbiologie is found a mixture of the botanical 
subject of insect visitors of flowers, the entomological subject of 
flower visits of insects, and collectors’ notes which have no definite 
relation to either subject but rather to the personal movements of 
collectors. He states that his work is based upon MULLER’s, but 
he fails to include data from works which follow MiLiEr’s method 
(MULLER’s Alpenblumen and MacLEop’s works on flowers of the 
Pyrenees and Flanders), and includes collectors’ notes which sup- 
press it, although such notes from French and Italian records are 
excluded as perhaps not justifying the labor of compilation. In a 
work which repeats MiLER’s lists for Low Germany for the third 
time American anthecological lists are suppressed. 
ANTHECOLOGICAL DATA.—These are lists of insect visitors made 
to show the species, their frequency, their efficiency as pollinators, 
and the possibility of their having some influence in determining 
the characters of the flowers. MwLLEr’s lists show these details. 
In the case of the bees he indicated the sexes, and whether they 
were sucking nectar or collecting pollen. To note the sexes is 
important because female bees fly longer than males and are more 
likely to make repeated visits. To note the fact of pollen-collecting 
is also important. A female bee will carry pollen all day from 
flowers on which the male rarely occurs. From observations at 
Carlinville the females of nest-making bees average 20.6 visits to 
the males 10.3. The inquiline bees show females 8.8 to males 8.0. 
In anthecology Mi1er’s lists are valuable as regards species and 
visits, but they fail to indicate the frequency. In 1908 I rejected 
ULLER’s method and adopted the practice of capturing the 
visitors as they came, noting species, and counting individuals. It 
is impossible to indicate the importance of insects to flowers by 
lists of species, because efforts to increase the lists involve 
an exaggeration of the importance of rare and exceptional cases. 
Botanical Gazette, vol. 73] [148 
