Lokalisatorischer Nachweis von Thermorezeptoren beiDorcus parallelepipedus L. undPyrrhocoris apterus L.

A temperature gradient is described in which the temperature of the air is measured. The “avoiding reaction” of normal and partially amputated insects is established, and a comparison of the results shows that inDorcus parallelpipedus L. (Coleoptera) the 3 distal segments of the antennae and the maxillar palps are sensitive to temperature. Of great importance is the last segment of the antennae inPyrrhocoris apterus L. (Heteropterae), because after its removal, the “avoiding reaction” suddenly increases at 4° C. Probably the trichoid sensillae are specialized receptors for temperature; their number seems to be important for the sensitivity to temperature.