The Acridiidae are considered to be exclusively vegetable feeders, each individual consuming a very large quantity of food. The mode in which the female deposits her eggs has been described by Riley,[222] and is now widely known, his figures having been frequently reproduced. The female has no elongate ovipositor, but possesses instead some hard gonapophyses suitable for digging purposes; with these she excavates a hole in the ground, and then deposits the eggs, together with a quantity of fluid, in the hole. She prefers hard and compact soil to that which is loose, and when the operation is completed but little trace is left of it. The fluid deposited with the eggs hardens and forms a protection to them, corresponding to the more definite capsules of the cursorial Orthoptera. The details of the process of oviposition and of the escape of the young from their imprisonment are of much interest. According to Künckel d'Herculais[223] the young _Stauronotus maroccanus_ escapes from the capsule by putting into action an ampulla formed by the membrane between the head and the thorax; this ampulla is supposed to be dilated by fluid from the body cavity, and is maintained in the swollen condition by the Insect accumulating air in the crop beneath it. In order to dislodge the lid of the capsule, six or seven of the young ones inside combine their efforts to push it off by means of their ampullae. The ampulla {291}subsequently serves as a sort of reservoir, by the aid of which the Insect can diminish other parts of the body, and after emergence from the capsule, penetrate cracks in the earth so as to reach the surface. Immediately after doing this the young _Stauronotus_ moults, the skin it casts being called by Künckel an amnios. The cervical ampulla reappears at subsequent moults, and enables the Insect to burst its skin and emerge from it. The process is apparently different in _Caloptenus spretus_, which, according to Riley, ruptures the egg-shell and works its way out by the action of the spines at the apex of the tibiae. This latter Insect when it emerges moults a pellicle, which Riley considers to be part of the embryonic membranes. Riley states that a female of _Caloptenus spretus_ makes several egg-masses. Its period of ovipositing extends over about 62 days, the number of egg-masses being four and the total number of eggs deposited about 100. The French naturalists have recently observed a similar fact in Algeria, and have ascertained that one of the migratory locusts—_Schistocerca peregrina_—may make a deposit of eggs at more than one of the places it may alight on during its migration.