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Psyche 
[September-December 
wards and downwards, so that the pointed processes come into 
contact with the skin. The head is then withdrawn tightly against 
the prothorax and rotated from a prognathous to a hypognath- 
ous position, deeply setting the antennal hooks. They are sharp 
enough to penetrate the skin, causing surprise, sudden pain and 
occasionally drawing blood (Figure 1C). Presumably a predator 
that grabbed one of these beetles would be similarly surprised, 
possibly injured, and might immediately drop the intended prey. 
The hoods withdraw easily from the skin once the body of the 
beetle has been released. 
The antennae of cerambycids are the longest known in the 
Coleoptera, both in an absolute sense and in relation to body 
size. Unlike the antennae of many other beetles, they are fully 
exposed and are often too long to be concealed in prothoracic 
grooves or other receptacles. Conceivably the use of antennae 
in defensive behavior is most likely to occur in insects the anten- 
nae of which are so large or so long that the alternative of con- 
cealment is no longer an option. We know of no other instance 
in which the antennae of an insect are used defensively. 
Tergiversation. 
When first seen, Oreodera glauca (Linnaeus) (Figure 2) ap- 
pears to be a light-colored, wedge-shaped insect with two con- 
spicuous legs directed “anteriorly.” The banded antennae appear 
to arise from a broad, distinct “head” bearing short horns. The 
entire effect is an illusion; the real head is located at the other 
end of the body. 
This illusion is achieved by a combination of color pattern 
and resting posture. The false “head” consists of the apices of 
the elytra, which are separated from the basal regions by a trans- 
verse, darkly pigmented line. False constrictions in the “cervical” 
region and elsewhere are produced by dark lateral markings. 
The true pronotum and head are somewhat darker in color and 
not easily recognized as such. The most important postural adap- 
tation is the positioning of the antennae, which serve two different 
functions. At the true head, the enlarged antennal bases cover 
the compound eyes, which otherwise would be visible and would 
destroy the reversed effect. The antennae are held closely along 
the sides of the body, and emerge from beneath the elytral apices, 
where they appear to arise from the false head. Finally, the third 
