and pass through a series of up to 10 moults. After mating, a period of 1-2 weeks may occur before the female starts laying eggs. She burrows into the soil to a depth of , ( has been seen in the laboratory), and lays a clutch of 25 to 60 eggs. Neoscapteriscus females then retire, sealing the entrance passage, but in Gryllotalpa and Neocurtilla species, the female has been observed to remain in an adjoining chamber to tend the clutch. Further clutches may follow over several months, according to species. Eggs must be laid in moist ground, and many nymphs die because of insufficient moisture in the soil. The eggs hatch in a few weeks, and as they grow, the nymphs consume a great deal of plant material either underground or on the surface. The adults of some species of mole crickets may move as far as during the breeding season. Mole crickets are active most of the year, but overwinter as nymphs or adults in cooler climates, resuming activity in the spring. Burrowing Mole crickets live almost entirely below ground, digging tunnels of different kinds for the major functions of life, including feeding, escape from predators, attracting a mate (by singing), mating, and raising of young. Their main tunnels are used for feeding and for escape; they can dig themselves under ground very rapidly, and can move along existing tunnels at high speed both forwards and backwards. Their digging technique is to force the soil to either side with their powerful, shovel-like fore limbs, which are broad, flattened, toothed, and heavily sclerotised (the cuticle is hardened and darkened). Males attract mates by constructing specially shaped tunnels in which they sing. Mating takes place in the male's burrow; the male may widen a tunnel to make room for the female to mount, though in some species, mating is tail-to-tail. Females lay their eggs either in their normal burrows or in specially dug brood chambers, which are sealed when complete in the case of the genus Neoscapteriscus or not sealed in the case of genera Gryllotalpa and Neocurtilla. Song Male mole crickets sing by stridulating, always under ground. In Gryllotalpa gryllotalpa, the song is based on an almost pure tone at 3.5 kHz, loud enough to make the ground vibrate 20 cm all round the burrow; in fact, the song is unique in each species. In G. gryllotalpa, the burrow is