ARENA HEADINGS, VANISHING BEARINGS AND HOMING TIMES BY ARGOGORYTES CARBONARIUS (HYMENOPTERA, SPHECIDAE) AFTER DISPLACEMENT IN OPEN OR CLOSED CONTAINERS

Arena headings, vanishing bearings and homing times were recorded in t he digger wasp Argogorytes carbonarius after displacement in 'open' or closed ('box') containers during two time periods. The periods differ ed in two ways: 1. wasps were assumed to be inexperienced with the rel ease sire during the first period, whereas during the second period th ey were assumed to be familiar with it; 2. during the first period the arena was open on all sides, during the second it was surrounded by a wall. All wasps chose arena headings and vanishing bearings in or clo se to the direction of the sun's azimuth during the first period and t here was no difference in homing times between 'open' and 'closed' was ps. These directions also were chosen by all wasps during the second p eriod in the arena and also by 'open' wasps at vanishing. 'Box' wasps, however, vanished preferably in the sector of home direction. They al so reached home faster than in the first period. The results are discu ssed with respect to landmark orientation and the path-integration hyp otheses.