There is nothing more to be expected from so rudimentary an instrument. We have nothing here similar to what the Grasshopper clan have shown us: no toothed bow, no vibrating membrane stretched into a drum. Let us, for instance, take a look at the Italian Locust (Caloptenus italicus, Lin.), whose apparatus of sound is repeated in the other stridulating Acridians. His hinder thighs are keel-shaped above and below. Each surface, moreover, has two powerful longitudinal nervures. Between these main parts there is, in either case, a graduated row of smaller, chevron-shaped nervures; and the whole thing is as prominent and as plainly marked on this outer side as on the inner one. And what surprises me even more than this similarity between the two surfaces is that all these nervures are smooth. Lastly, the lower edge of the wing-cases, the edge rubbed by the thighs which serve as a bow, also has nothing particular about it. We see, as indeed we do all over the wing-cases, nervures that are powerful but devoid of any rasping roughness or the least denticulation. What can this artless attempt at a musical instrument produce? Just as much as a dry membrane will emit when you rub it. And for the sake of this trifle the insect lifts and lowers its thighs, in sharp jerks, and is satisfied with the result. It rubs its sides very much as we rub our hands together in sign of contentment, with no intention of making a sound. That is its own particular way of expressing its joy in life. Examine it when the sky is partly obscured and the sun shines intermittently. There comes a rift in the clouds. Forthwith the thighs begin to scrape, increasing their activity as the sun grows hotter. The strains are very brief, but they are renewed so long as the sunshine continues. The sky becomes overcast. Then and there the song ceases, to be resumed with the next gleam of sunlight, always in brief spasms. There is no mistaking it: here, in these fond lovers of the light, we have a mere expression of happiness. The Locust has his moments of gaiety when his crop is full and the sun benign. Not all the Acridians indulge in this joyous rubbing. The Tryxalis (Truxalis nasuta, Lin.), who sports a pair of immensely elongated hind-legs, maintains a gloomy silence even under the most vigorous caresses of the sun. I have never seen him move his shanks like a bow; he seems unable to use them—so long are they—for anything but hopping. Dumb likewise, apparently as a consequence of the excessive length of his hind-legs, the big Grey Locust (Pachytilus cinerescens, Fabr.) has a peculiar way of diverting himself. The giant often visits me in the enclosure, even in the depth of winter. In calm weather, when the sun is hot, I surprise him in the rosemaries, with his wings unfurled and fluttering rapidly for a quarter of an hour at a time, as though for flight. His twirling is so gentle, in spite of its extreme speed, as to create hardly a perceptible rustle.