WORLD OF INSECTS

Evening Post, Volume CXXV, Issue 48, 26 February 1938, Page 26

WORLD OF INSECTS

FASCINATING STUDY.

A study of insects opens up a fascinating and unexpected world, but quite how fascinating and strange is perhaps not fully realised by most people until they come across a book like "Grassroot Jungles," by Edwin Way Teale, in which pen and camera have combined forces in an extraordinarily interesting way. The insect population ot the earth is incredibly large. Nine-tenths of all the living creatures on the face of the earth, we are told, are insects. Every square mile in the air above the earth is inhabited by twenty-five million of them, and each acre of soil harbours 3,500,000; Man may exceed them in Strength, but the insects have the ability to endure, and their brief life cycle enables them to adapt themselves to changing conditions where a larger and slower organism would perish. Four-fifths of the insects] found as fossils belong to orders and families that exist today. To study them opens vistas through which man, the creature of an hour, may look into the immeasurable depths of past and future, from the days when monstrous moths with the size and wingspread of hawks flew over the tree ferns of the Carboniferous Age to the speculatively possible time when insects may be the last form of life surviving on a frozen world under a slowly cooling sun. The damage done annually by insects runs into millions of pounds, although only a few hundred of the many thousand species are enemies of mankind.' After describing insects in general, the author describes their methods of eating—the butterfly's watch-spring proboscis, the honey bee that laps with its tongue, the mandibles of the paper-making wasp, the May fly that never eats at all. He tells how their songs are made —"some insects employ the principle of the violin, others that of the flute; still others that of the drum." Their blood is green or yellow; ants follow their paths; mosquitoes and midges hear, with antennae rather than eyes and ears; many-lensed eyes, each making a separate image, combine in a mosaic, while single eyes may serve to distinguish light from dark. Bees recognise colour, "the eye of the butterfly can see far more than the insect's brain can understand."

From this Mr. Teale proceeds to tell something of the different orders in turn—the dragonflies, oldest of insects, contemporary of the dinosaurs; the monarch butterflies, which play their part in the balance of, nature by holding the milkweed in check; the aphides —weak but persisting through their fertility—which despite their enemies cause a staggering loss to farms and vineyards; moths, with their silk; the Polyphemus, with its single eye upon each wing, designed perhaps for camouflage, to direct the attention of enemies away from vital spots; spiders, the first spinners and weavers, which "applied the principles of geometry long before Euclid," and which recently played their part in the building of the Panama Canal, when their silk was used "for cross-threads in the transits of the surveyors." There are spiders which build under water and carry air down with them, spiders that build nests with hinged trapdoors; in autumn migrations spiders "ride the air currents, floating at the end of long threads."

He tells of bumblebees that store honey in pots, that sit on their eggs Ike hens; of frog hoppers, tree hoppers, ambush bug and candle head (with beak like a tiny duck), the seventeen-year cicada, with the longest life cycle of all insects (called "locusts" by the Pilgrims, who thought in encountering them of the biblical plague).; the community life of ants and some of its still unsolved problems; .wasps, with their intelligence and apparent powers of reasoning; crickets, kept in China for their music and for the sport of cricket fighting, with elaborate ritual of trainers and diet, champions often being buried in tiny silver coffins. Sound films of the cricket's song made at the American Museum of Natural History show that "the notes are in tHe octave above piano range and consist of a series of beautifully executed 'slurs' such as only an expert violinist can produce."