| 
4 
4 
k 
3 
; 
1899] FLOWERS AND INSECTS 45 
which has the effect of giving them some standing among the 
fundamental principles of flower-and-insect ecology. 
The existence of branched hairs in the bees may properly be 
interpreted as an adaptation for carrying pollen, because the 
bees use them for that purpose, and the importance of the hairs 
is evident, in view of the economy of the insects. They cannot 
in any way be interpreted as existing for the benefit of the 
flowers. It could be of no advantage to flies and birds to carry 
pollen, since they make no use of it. However, it might be 
claimed that these guests derived an indirect benefit from the 
pollination of their favorite plants. But their relations to flowers 
are not close enough to make their existence depend upon the 
pollination and preservation of any particular species. 
An examination of the inquiline bees will lead to the conclu- 
sion that the several genera are not related to one another but 
have arisen independently from different groups of host bees. 
It will also lead to the conclusion that they have all lost their 
hairy coats, or tend to do so, as in Psithyrus. To my mind the 
fact that these bees began to lose their coats as they abandoned 
their pollen-collecting habits, involves a clear refutation of the 
claims that any structures on flies and birds were developed for 
the purpose of carrying pollen. 
CARLINVILLE, TEL. 
