1988] 
Holldobler — Chemical communication 
147 
Figure 4. Meranoplus hirsutus workers in defensive posture, a. Workers which 
were mechanically disturbed, immediately arch up their gaster and extrude a droplet 
of Dufour’s gland secretions on the exposed sting, b. The same behavior can be 
observed in workers guarding a piece of prey. 
