to fill the room that is under treatment. This smoke kills or so stupefies the insects that they will not bite. Pyrethrum powder is a preparation of the plant Pyrethrum roseum, and is sometimes sold as Persian Insect Powder or Dalmation Powder; it can be bought at any drug store for about thirty-five cents a pound. It is a very fine, light powder; and an ounce of it will go a long way, making a large volume of smoke. A pyrethrum smudge or smoke may be started by covering a live coal, taken from the kitchen stove, with the powder, first placing the coal upon a small shovel, so that it may be moved about conveniently without danger of setting anything on fire. The pyrethrum will
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| Fig. 8. Profile of Anopheles punctipennis (Female). Three times larger than life. Showing the characteristic resting position of this mosquito. | Fig. 9. Profile of a Culex Mosquito (Female). Three times larger than life. |
quickly begin to smoulder and give off a dense smoke. All that is now necessary is to add from time to time a pinch of the powder as occasion requires, merely keeping the smouldering ashes covered so that they will give off a smoke. People are frequently annoyed and sometimes driven into their houses on summer evenings by the persistent attacks of mosquitoes. On such occasions, pyrethrum powder can often be used to advantage; and the smoke from a small quantity of the powder kept smouldering upon the piazza will drive away most, if not all, of the pests, thus making it possible to enjoy an evening out doors in comfort, when otherwise life would be unbearable except behind the protection of screens.
The Anopheles, or malarial mosquitoes, though not very common (see Figs. 7 and 8), are breeding quite abundantly in many parts of this country; and by referring to the accompanying photographs, particularly the ones in profile, it will be seen that there is quite a difference between the malarial and the common, or Culex, mosquitoes.
