72 ENTOMOLOGICAL NEWS. [Feb., 14 
4, H. placida 4. The best of these shows eight less than the 
average and may be regarded as fragmentary. 
If a bee limits itself to a given flower, it gains the immediate 
advantage of being able to anticipate other bees in their visits 
to the chosen plant. It may increase this advantage by locating 
its nests near the flowers. To humanize, it may concentrate its 
attentions upon the flowers so as to get to them first, learn 
how to manipulate the pollen better than other bees, and 
finally develop special structures which will increase the ad- 
vantage. 
I have pointed out that some oligotropes which collect large 
pollen have loosely plumose scopae which are better adapted 
to collect and hold the large grains, while some others which 
collect the fine pollen of Compositae have densely plumose 
scopae. 
Anthedon compta, an oligotrope of Oenothera, whose pollen 
grains are hard to collect on account of being connected by 
threads, has scopae of long simple bristles quite different from 
its nearest relatives. After doing the best it can on the flower, 
it goes to the stem and turns head downwards so as to work 
the cobwebby pollen into its scopae. Other bees collect the 
pollen, but Anthedon surpasses them all in the facility with 
which it does so. 
The anthers of Verbena are included in a slender tube and 
above them is a circle of hairs as if intended to prevent the 
pollen from being extracted. Ordinary bees can only collect 
the pollen which adheres to their proboscides. Verbenapis 
verbenae has its front tarsi provided with curled bristles. 
When collecting pollen the bee thrusts both front legs into the 
tube of the corolla and drags out the pollen with its front 
tarsi. 
There are 223 indigenous nest-making bees. One species, 
flying throughout the season and fitted about like Apis, except 
for flowers of unusual construction, might collect nearly as 
much pollen and support nearly as many individuals as all of 
the 223 together. It would be to the advantage of this bee to 
become as polytropic as possible, and, as the number of in- 
dividuals increased, to extend its visits to the most difficult 
