1934] Sting of the Male Wasp , Monobia quadridens 245 
THE STING OF THE MALE WASP, MONOBIA 
QUADRIDENS 
By Phil Rau 
Kirkwood, Mo. 
The females of solitary wasps have a functional sting, 
while male wasps are devoid of stings, but often the latter 
are not devoid of the desire to sting. In picking up males of 
Sceliphron csementarium and Chalybion cxruleum, one oc- 
casionally notes attempts to pierce one’s flesh with the tip 
of the abdomen. Stinging by the males in these two species 
is not possible, but it may prove useful in frightening an 
enemy. 
In Monobia quadridens the female can sting one’s hand 
and cause a slight pain, but I was indeed surprised when I 
picked up a male to find him also able to inflict pain by pierc- 
ing the flesh with the tip of his abdomen. The pain resem- 
bles that of a sharp needle prick and is over after a few 
seconds, since of course no poison is injected. The attempt 
at stinging by the male fulfills a purpose similar to the sting 
by the female because it effects the release and escape of the 
insect; the same behavior in its natural habitat, when 
trapped by an enemy, would prove beneficial to the male. 
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