Read Great Hike; or, The Pride of the Khaki Troop Page 26

  THE ORDER DIPTERA.

  This order includes all the true flies or insects having but two wings.There is probably no other order of insects that are more injurious tothe health of human beings. The housefly, because of its habits, is avirulent pest in the spreading of disease and it has been discoveredthat certain mosquitoes carry the germs of malarial and yellow fevers.

  MOSQUITOES.

  Up to the year 1900 little had been known about these insects. Sincethen it has been discovered that one genus is responsible for thetransfer of malarial fever and another variety is the sole means of thespreading of yellow fever. Mosquitoes are found in any locality wherestagnant standing water allows them the opportunity to breed. Theireggs are laid in a flat mass on the surface of the water, and each ofthese masses contains from 200 to 400 eggs. The young mosquitoes issuefrom the under side of the eggs, coming to the surface frequently tobreathe, which they do by means of a long tube at the end of the bodywhich is thrust up above the surface of the water. In many localitiesboy scouts have been interested in exterminating mosquitoes, the mostsuccessful methods being either the abolition of their breeding places,the flooding of surfaces of stagnant water with kerosene, or theintroduction of fish into fishless ponds. In a mosquito crusade everyreceptacle for standing water must be found and either destroyed ortreated with kerosene.

  MIDGES.

  Midges are small or minute flies; swarms of them are commonly seen indamp localities in the summer.

  FLIES.

  Horseflies are unusually abundant in the neighborhood of ponds andstreams.

  The Robber Flies, or bee-killers, are the hawks of the insect world,preying upon their victims on the wing. In flying an insect is likely tobecome the victim to their sharp little dagger, which they carry intheir beak. It is said that they will frequent a favorite position neara beehive and make frequent trips back and forth, and hundreds of emptybodies of bees are found beneath this perch.

  The Dancefly is so called because of the up-and-down movement which theymake in their swarms.

  The Housefly. These insects are highly injurious to human beings becauseof their agency in spreading germs of such diseases as typhoid fever andAsiatic cholera. It has been discovered recently that germs ofinfantile paralysis are conveyed by the housefly.

  THYSANOPTERA.

  To this order belong very small insects known as "thrips." They arefound in large numbers in flowers and in the heads of grain,chrysanthemum, hydrangea, orange-blossom, cabbage leaf, cauliflower,squash, turnips and other plants.