All his life long he tunnels beneath the ground from place to place. When you think of how long it would take you, even with the best tools, to dig a hole in the ground big enough to crawl into, you will get some idea of the power which these two front legs, four-pointed like a spading fork, must have, to enable such a creature to disappear into the ground in a few seconds as he does. These paws, proportionately many times more powerful than bears' paws, are snippers too, for moving back and forth behind them is a sharp-edged instrument which, like the shuttle-bar on a mowing machine, shears off the grass roots which interfere with the mole cricket's progress through the ground. The poor defenseless angleworms must fall an easy prey to such a foe as this! Upon the first joint of each clumsy front leg, it has a narrow slit-like ear which is but faintly visible in the photograph. Can you imagine a male and female calling to each other through the long and winding passageways beneath the ground? Possibly they call to each other only in the night-time, on the rare occasions when they venture out above the ground. He is a curious creature with eyes that are only rudimentary and a noxious smell that he emits if he is touched. The female excavates a chamber near the surface of the ground and lays her eggs in it to be incubated by the sun's heat, as are most insects' eggs. For some time it was supposed that both parents devoured their progeny, as many as 90 per cent being eaten up, but a French observer, Monsieur Decaux, has found that the male alone is the cannibal and the mother, far from doing this, watches over them and when they hatch she feeds the little ones with bits of plant roots, earthworms and the larvæ of various insects. The discovery of one of these mole crickets is really an event. Most people see but one or two in all their lives. In Porto Rico, however, there is a form with longer wings which eats the roots of sugar cane, tobacco and other crops so that the "changa," as it is called, is considered the most serious insect pest in the island. [Illustration] THE COCKROACH (_Blatella germanica_, Linn.) In carboniferous times this was a dominant creature, crawling over the giant club mosses and tree ferns which composed the marshy vegetation of the young world. Today it crawls over the cracker-box and makes its way through every crevice in the kitchen and is, of all the creatures of our houses, the most detested. This is the German cockroach, an importation from Europe, which has spread around the world, and which New Yorkers know as the croton bug. Its long, spiny legs are built for the scurrying for which it is noted, while its slippery body enables it to squeeze through crevices and holes. It carries its head tucked under its body, as if looking for food, and its whiplike antennæ, always in motion, detect at long range the presence of anything edible which can be crammed into its capacious crop.