Humidity Reactions ofMelanoplus bivittatus(Say) andCamnula pellucida(Scudd.) (Orthoptera, Acrididae): Reactions of Normal Grasshoppers

Abstract

Nymphs of the clear-winged grasshopper,Camnula pellucida(Scudd.) have been observed to evacuate local habitats by marching (11). Except for a few stragglers, apparently all occupantsof the habitat moved in the same direction. Rarely, if ever, did these marches continue for more than 300 yardsin one direction, nor did the insects show much tendency to maintain identity as a band; nevertheless, the capacity of this species to march was clearly shown. The marches always occurred during the day and when the temperature was above 20°C. (8). In all recorded cases the nymphs moved into a cooler and more humid area. The authorhas not observed, or received reports of, instances of marching in the comparatively sluggish two-striped grasshopper,Melanoplus bivittatus(Say).