Classicly

On the other hand, I know of another function, which is very easily observed when the Scorpion meanders, belly uppermost, over the wire trellis of my dish-covers. When he is at rest, the two combs are laid flat on the abdomen, behind the legs. The moment he begins to walk, they stick out on either side, at right angles to the body, like the naked wings of an unfledged nestling. They sway gently up and down, reminding us of the balancing-pole of an inexperienced rope-dancer.4 If the Scorpion stops, they are at once retracted, fall back upon the belly and cease to move: if he resumes his walk, they are at once extended and again begin their gentle oscillation. The animal therefore seems to use them at least as a balancing mechanism.