Elementary biology; an introduction to Elementary biology; an introduction to the science of life elementarybiolog00grue Year: 1924 INSECTS AND HUMAN WEALTH 413 only insect that supplies food to man is the honeybee, whose honey has been used by man for many centuries. 446. Insect products. The wax obtained from bees is of great practical value, but it is coming to be replaced more and more by paraffin, which is obtained from petroleum. Another insect product of growing importance, and one for which no satisfactory sub- stitute has yet been found, is lac. The lac is used as a dressing for wood
Elementary biology; an introduction to Elementary biology; an introduction to the science of life elementarybiolog00grue Year: 1924 INSECTS AND HUMAN WEALTH 413 only insect that supplies food to man is the honeybee, whose honey has been used by man for many centuries. 446. Insect products. The wax obtained from bees is of great practical value, but it is coming to be replaced more and more by paraffin, which is obtained from petroleum. Another insect product of growing importance, and one for which no satisfactory sub- stitute has yet been found, is lac. The lac is used as a dressing for wood and other materials, as shellac, as a stif- fening for felt in the making of hats, as an insulating var- nish in electrical work, in the making of lithographer's ink and of sealing wax, and in increasing quantities in the manufacture of phonograph records. The cochineal, another member of the scale-insect family, furnishes a beautiful red dye, which was formerly used in large quantities. This source of supply is of de- clining economic importance because of the rapid development of the anilin-dye industry. The whole silk industry rests upon the fiber obtained from the cocoon covering of the silk moth. Although the chemists have devised ingenious processes for making artificial silk out of cotton and out of wood, we shall probably continue to cultivate the silk moth for a long time to come. Many of the beetles may be considered as useful, since they destroy large amounts of dead animal remains, as do Fig. 214. Destruction wrought by ants Part of a post completely ruined by the excavations of carpenter ants. There are several species of Campoiiotiis and of other genera which are known to bore into wood. (From photograph by New York Botanical Garden)
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