Hymenoptera aculeata from Majorca and Spain. 665 
and of V. bombylans to the red-tailed and banded humble- 
bees have been promoted by the special associations which 
render the models peculiarly feasible in each respective 
case. These Diptera live in the same habitats as their 
models, and may be seen visiting the same flowers; they 
fly from nest to nest to deposit their eggs, and their first 
flight on emergence from the puparium is made from the 
home of an Aculeate community. It is obvious that their 
mode of life bears a strong superficial resemblance to 
that of their respective hosts, and that mimetic likeness 
to these hosts would be far more convincing and advan- 
tageous than to other species of Aculeates. 
Although mimicry is not necessarily dependent on a 
mode of life which brings an insect into intimate relation- 
ship with some widely-different form possessed of special 
means of defence, yet such associations are very commonly 
attended by mimicry. In this note it has been seen that 
mimetic likeness may result when the relationship is 
that between captor and prey, whether the prey be 
defended by a sting or by some nauseous quality—that it 
may result when the association is that of scavenger to an 
Aculeate host. 
iy Beek: 
TRANS. ENT. SOC. LOND. 1904,—PART Ill. (SEPT.) 43 
