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[March 
contents, they also qualify as spraying glands. We know of no other 
tenebrionid glands that operate in this way. Eversible glands are 
common, but they are generally shorter than those of Adelium and 
do not eject spray on extrusion. Spraying does occur, but only from 
non-eversible glands, as in Eleodes (Eisner, 1966). The peculiar 
habit of Adelium of relaying secretion by way of its appendages is 
not unique. Other tenebrionids are also said to use their legs for 
administration of secretion (Tschinkel, 1972), and comparable be- 
havior has been reported for opilionids (Eisner et al., 1971b) and 
Hemiptera (Remold, 1962). 
Many insects produce chirps or other “disturbance” calls when 
they are molested. Cerambycid beetles, for example, very generally 
show this property, as do other beetles, cockroaches, Hemiptera, 
adult and immature Lepidoptera, and members of most other groups, 
including non-insectan arthropods (references in Alexander, 1967; 
Haskell, 1961; Roth and Hartman, 1967; Tuxen, 1967). The 
sounds are generally believed to be defensive, but it is by no means 
clear how precisely they act in this capacity. Convincing evidence 
has been advanced to account for the function of the calls in arctiid 
moths. These insects are chemically protected (Bisset et al., i960) 
and hence presumably distasteful, and they emit sounds, rich in ultra- 
sound, in response to the echolocating chirps of bats (Blest et al., 
1963). Bats turn away from the calls, presumably because they have 
learned on the basis of previous experience with the moths that a 
prospective meal that “protests” audibly is distasteful (Dunning and 
Roeder, 1965; Roeder, 1967). The sounds, then, act as acoustical 
aposematic signals, operative in the dark just as visual aposematic 
adornments supposedly operate in the light. Defensive calls generally, 
to the extent that they are produced by chemically or otherwise pro- 
tected insects and induced by encounters with predators, may function 
in this way. They might certainly do so in Adelium pustulosum, a 
furtive animal most likely to meet its enemies in darkness. But the 
calls need not only serve for acoustical reinforcement of a concomi- 
tant defense. They could also be intrinsically deterrent to predators, 
perhaps only to some, or they might function socially — as do “alarm” 
sounds in termites and ants (Howse, 1964; Markl, 1967, 1969; 
Markl and Fuchs, 1972) — to alert conspecifics to states of emer- 
gency. But these possibilities, like so many other functional sug- 
gestions that have been advanced for disturbance calls, remain to be 
proven. One wonders what predators might be affected by the chirps 
of Adelium, although criteria for compiling a list of enemies are lack- 
