The exact similarity of the two wing-cases is worthy of attention. I can see clearly the function of the upper bow and the four sounding-areas which it sets in motion; but what is the good of the lower one, the bow on the left wing? Not resting on anything, it has nothing to strike with its hook, which is as carefully toothed as the other. It is absolutely useless, unless the apparatus can invert the order of its two parts and place that above which was below. After such an inversion, the perfect symmetry of the instrument would cause the necessary mechanism to be reproduced in every respect and the insect would be able to stridulate with the hook which is at present unemployed. It would scrape away as usual with its lower fiddlestick, now become the upper; and the tune would remain the same. Is this permutation within its power? Can the insect use both pot-hooks, changing from one to the other when it grows tired, which would mean that it could keep up its music all the longer? Or are there at least some Crickets who are permanently left-handed? I expected to find this the case, because of the absolute symmetry of the wing-cases. Observation convinced me of the contrary. I have never come across a Cricket that failed to conform with the general rule. All those whom I have examined—and they are many—without a single exception carried the right wing-case above the left. Let us try to interfere and to bring about by artifice what natural conditions refuse to show us. Using my forceps, very gently, of course, and without straining the wing-cases, I make these overlap the opposite way. This result is easily obtained with a little dexterity and patience. The thing is done. Everything is in order. There is no dislocation at the shoulders; the membranes are without a crease. Things could not be better-arranged under normal conditions. Was the Cricket going to sing, with his inverted instrument? I was almost expecting it, appearances were so much in its favour; but I was soon undeceived. The insect submits for a few moments; then, finding the inversion uncomfortable, it makes an effort and restores the instrument to its regular position. In vain I repeat the operation: the Cricket’s obstinacy triumphs over mine. The displaced wing-cases always resume their normal arrangement. There is nothing to be done in this direction. Shall I be more successful if I make my attempt while the wing-cases are still immature? At the actual moment, they are stiff membranes, resisting any changes. The fold is already there; it is at the outset that the material should be manipulated. What shall we learn from organs that are quite new and still plastic, if we invert them as soon as they appear? The thing is worth trying.