ABSTRACT
The physiological characteristics of the wing musculature of insects have been but little investigated. Solf (1931) has given a brief account of the responses of the dorsal longitudinal muscles of Gryllotalpa vulgaris (L.) to direct electrical stimulation. A more extensive study has been made by Heidermanns (1931) of the responses to direct electrical stimulation of the wing muscles of Aeschna coerulea (Strom). The latter author found that at a stimulation frequency comparable with that of the normal wing beat of the dragonfly, the muscles were in a partial tetanus. He concluded that this was their normal condition in flight. More recently, Pringle (1949) has found that potentials recorded from the wing muscles of Calliphora occur at a lower frequency than the wing movements. He concluded that these flight muscles were highly specialized, and that impulses from the nervous system activated rather than excited the muscles. Similar observations have been made by Roeder (1950, 1951) on Vespa, Lucilia and Tabanus. In Periplaneta and the moth Agrotis, however, Roeder recorded a single muscle potential for each cycle of the wing beat. He concludes that in the latter two species the wing-beat frequency was such as to permit a conventional neuromuscular system to move the wings.
