Terminal velocity of the first instarEctropis excursaria (Guenee) (Lepidoptera: Geometridae)
The terminal velocity of first instarEctropis excursaria, determined in a part mechanical part electrical apparatus, were 114±12 cm/s and 118±12·5 cm/s for two different heights. Terminal velocity decreased exponentially with increased silk lengths. For a given length of silk there wsa a significant difference in the terminal velocity of live and anaesthetised insects. The significance of these results to the understanding of the wind dispersal of first instar caterpillars is discussed.