Productive farming . ss. Male cecropia mothbove, male poljphemus nioth below. S. Office of Experiment Stations). changes take place in the life of the organisms which cantake place nowhere else. If the mosquitoes were extermi-nated the organisms of malaria could not thrive. When amosquito attacks a well person some of the germs of malariaare apt to be forced into the blood of the person by the suckingmouth parts of the insect. Thus every new case of malariais started. INSECTS 209 The remedy is easy to understand. If the ponds or poolsof standing water are taken care of, the malarial mosqu
Productive farming . ss. Male cecropia mothbove, male poljphemus nioth below. S. Office of Experiment Stations). changes take place in the life of the organisms which cantake place nowhere else. If the mosquitoes were extermi-nated the organisms of malaria could not thrive. When amosquito attacks a well person some of the germs of malariaare apt to be forced into the blood of the person by the suckingmouth parts of the insect. Thus every new case of malariais started. INSECTS 209 The remedy is easy to understand. If the ponds or poolsof standing water are taken care of, the malarial mosquitoeswill not be able to find suitable breeding places. Thesestagnant waters may be drained away, or covered with crudeoil, or fish may be kept in them to feed upon the and other vessels of water must be emptied or coveredwith oil. Houses should be screened to keep out is believed that the malarial mosquitoes are never activeduring the day when the sun is shiningi Pia. 126 y, Fig. Fig. 125.—Malarial mosquito wriggler at left, common at right. (Div. Ent.,tr. S. Dept. Agrio.) Fig. 126.—Malarial mosquito below, common above. (Div. Ent., U. S. Dept,Agric.) It is not difficult to distinguish the malarial mosquitoesfrom the other common forms. The position of the wrigglersin the water when at rest is parallel to the surface of thewater, while the resting position of the common mosquitowriggler is nearly perpendicular to the surface of the water(Fig. 125). When the adult malarial mosquito is attackinga person the body is nearly perpendicular to the surfaceattacked; while with the common mosquito it is nearly levelwith the surface (Fig. 126). Yellow fever is also spread by mosquitoes of a particularU 210 PRODUCTIVE FARMING group (Fig. 127). This is a common form in the bodies of the insects are striped with bands of blackand white. By removing the breeding places of these insectsthe yellow fever disease has at times been stamped out i
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