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Introduction to the Study of Science 



in exterminating the Anopheles, which transmits malaria, and 

 the Stegomyia, which transmits yellow fever. 



264. Life history and habits of the mosquito. As is the 

 case with all winged insects, the several varieties of the mosquito 

 have a life story which is the same in all general features. The 

 study of the common Culex or domestic variety of the mosquito, 

 which is selected for convenience, will provide, therefore, a 

 sufficient foundation for the understanding of the slight vari- 

 ations in the Anopheles and the Stegomyia. The experiments 

 outlined will afford opportunity to verify and supplement the 

 brief account here presented of its life history and habits. 



265. The eggs. All mosquitoes lay their eggs in water, 

 usually in that which is stagnant or still and rich in food 



FIG. 161. Life story of the Culex mosquito. Compare each stage of the 

 Culex with the corresponding stage of the Anopheles. 



materials for the young. The eggs of the Culex cohere in rafts 

 or masses (Fig. 161). The color of the upper surface of the 

 eggs is gray to brown or sooty in appearance, and of the under 

 surface silvery to water-white. Each mass may consist of from 



