bo 
bo 
ADAPTIVE COLORATION 
nr 
plexippus. The latter species, or ‘‘ model,” appears to be un- 
molested by birds, and the former species, or ‘‘ mimic,” is 
thought to secure the same exemption from attack by being 
mistaken for its unpalatable model. The common drone-fly, 
Eristalis tenax (Fig. 244, B) mimics a honey bee in form, size, 
Fic. 244. 
Protective mimicry. A, drone bee, Apis mellifera; B, drone fly, Eristalis tenax. 
Natural size. 
coloration and the manner in which it buzzes about flowers, 
in company with its model; it does not deceive the kingbird 
and the flicker, however. Some Asilidze are remarkably like 
bumble bees in superficial appearance and certain Syrphus flies 
mimic wasps with more or less success. The beetle Casnonia 
bears a remarkable resemblance to the ants with which it lives. 
The classic cases are those of the Amazonian Heliconiidze 
and Pieridz, in which mimicry was first detected by Bates. 
The Heliconiidz (Frontispiece, Fig. 1) are abundant, vividly 
colored and eminently free from the attacks of birds and other 
enemies of butterflies, on account of their disagreeable odor 
a family fundamentally dif- 
and taste. Some of the Pieridz 
ferent from Heliconiide—imitate (Frontispiece, Fig. 2) the 
K ran) 
protected Heliconiidz so successfully, in coloration, form and 
flight, that while other Pieridze are preved upon by many foes 
aD » » d ’ 
the mimicking species tend to escape attack. 
The family Heliconidz, referred to by Bates, comprised 
what are now known as the subfamilies Heliconiunz, Itho- 
miinz and Danainz; similarly, Pieridze and Papilionidze are 
16 
