Wing profile sections through the wingbeat and across the wing for the (a–d) hindwing and (e–h) forewing of locust L4. ((a,e) 20% wing length, (b,f) 40% wing length, (c,g) 60% wing length and (d,h) 80% wing length.) These profile sections are typical of all the locusts that we made measurements for. The leading edge of the wing is at the left of each profile. The vertical bars through the sections indicate the positions of major wing veins. The asterisks denote the location of the maximum absolute chord height, the position of which varies discontinuously through the stroke. Note the decrease in the camber along the wing, and the marked changes in the camber through the stroke. See the text for discussion. The angle to the left of each profile section is the instantaneous local angle of incidence.