Turpentine vapor takes longer than naphtha to evaporate, and will be detected from furniture in a Avarm room for some time. It is an irritant to the skin of certain persons. Be careful that live specimens do not escape. Examine in small vials or small boxes, where they can be controlled. Lesson I Materials. — Typical insects of large size. The locust or " grasshopper," or the large cockroach will show the char- acteristics of the insects with direct metamorphosis. The butterflies or moths furnish examples of insects giving indirect metamorphosis. Magnifying glasses. German insect pins or long, slender " mourning " pins or needles. Flowers of Pyrethrum or related species. Samples of pure insect powder. Diagrams and charts for illustration of parts and related forms. General Information or Introduction. — The healthy house is the clean house. The clean house must stand upon clean foundations, amid clean surroundings. It must be built of clean materials, supplied with clean air, clean water, clean food, and clean furnishings. All of these must then be kept clean in order that the clean occupants may reach that height of sanitary cleanness which is health. If all houses 322 HANDBOOK OF DOMESTIC SCIENCE at all times could show a bill of health with the above items, there would be no need of any study of household pests. It is because any house may sometimes depart from the standard that it is necessary to study the forms, life history, and habits o£ insects which invade the house, and the pre- ventive and remedial methods which govern the protection of the household and household property. Only a few species out of the many which the insect world furnishes come under the head of Household Pests. The student of domestic science should seek all possible information concerning insect life in general, besides that special knowledge which applies to the few which are likely to be met with as foes. The life history of insects is especially interesting because the periods of growth or metamorphoses are often more apparent than in the higher animals and man. Four dis- tinct stages appear — egg, larva, pupa, imago. When between the egg and the adult there is a stage where no feeding and no movement from place to place goes on, the changes or the metamorphosis are said to be " indirect " ; where between egg and adult there is no quies- cent stage, the metamorphosis is " dwect.'' Some writers still retain the older terms " complete " for " direct " ; " in- complete " for " indirect." The egg is always minute, sometimes microscopic; it gives birth to the larva, commonly known by one of several names, grub, worm, maggot, caterpillar, wriggler, etc. The larva may or may not moult once or several times before passing into the next stage, the quiescent or pupal form. Each moult means an increase in size, for when the little body gets too big for its skin, a new, soft, and flexible skin has already formed beneath the old. The old skin is rup- tured, and the larva emerges. Man has to remove his old clothes and then put on the new. Insects come out of their HOUSEHOLD PESTS 323 old clothes already dressed in the new suit, perfectly fitted externally and internally.

AI-modernized reading of the original text

Turpentine vapor takes longer than naphtha to evaporate, and will be detected from furniture in a Avarm room for some time. It is an irritant to the skin of certain persons. Be careful that live specimens do not escape. Examine in small vials or small boxes, where they can be controlled. Lesson I Materials. — Typical insects of large size. The locust or " grasshopper," or the large cockroach will show the characteristics of the insects with direct metamorphosis. The butterflies or moths furnish examples of insects giving indirect metamorphosis. Magnifying glasses. German insect pins or long, slender " mourning " pins or needles. Flowers of Pyrethrum or related species. Samples of pure insect powder. Diagrams and charts for illustration of parts and related forms. General Information or Introduction. — The healthy house is the clean house. The clean house must stand upon clean foundations, amid clean surroundings. It must be built of clean materials, supplied with clean air, clean water, clean food, and clean furnishings. All of these must then be kept clean in order that the clean occupants may reach that height of sanitary cleanness which is health. If all houses at all times could show a bill of health with the above items, there would be no need of any study of household pests. It is because any house may sometimes depart from the standard that it is necessary to study the forms, life history, and habits of insects which invade the house, and the preventive and remedial methods which govern the protection of the household and household property. Only a few species out of the many which the insect world furnishes come under the head of Household Pests. The student of domestic science should seek all possible information concerning insect life in general, besides that special knowledge which applies to the few which are likely to be met with as foes. The life history of insects is especially interesting because the periods of growth or metamorphoses are often more apparent than in the higher animals and man. Four distinct stages appear — egg, larva, pupa, imago. When between the egg and the adult there is a stage where no feeding and no movement from place to place goes on, the changes or the metamorphosis are said to be " indirect " ; where between egg and adult there is no quiescent stage, the metamorphosis is " dwect.'' Some writers still retain the older terms " complete " for " direct " ; " incomplete " for " indirect." The egg is always minute, sometimes microscopic; it gives birth to the larva, commonly known by one of several names, grub, worm, maggot, caterpillar, wriggler, etc. The larva may or may not moult once or several times before passing into the next stage, the quiescent or pupal form. Each moult means an increase in size, for when the little body gets too big for its skin, a new, soft, and flexible skin has already formed beneath the old. The old skin is ruptured, and the larva emerges. Man has to remove his old clothes and then put on the new. Insects come out of their old clothes already dressed in the new suit, perfectly fitted externally and internally.

Handbook of domestic science and household arts for use in elementary schools