. Sanitary entomology; the entomology of disease, hygiene and sanitation. s. Culex quinquefasciatus Say, the dengue fever mosquito, la3^s its eggsin boat-shaped masses floating on the surface of the w^ater. It may layfrom 180 to 350 in a mass in 7 to 11 rows. The eggs hatch after one tothree days. An egg mass of a Culex mosquito is shown in fig. 48. Anopheles crucians Wiedemann has an elongate fusiform egg(fig. 49c) slightly more tapered toward one end, both ends dorsal surface is granular, the ventral surface coarsely hexagonallyreticulate. The floats occupy about half the sides i
. Sanitary entomology; the entomology of disease, hygiene and sanitation. s. Culex quinquefasciatus Say, the dengue fever mosquito, la3^s its eggsin boat-shaped masses floating on the surface of the w^ater. It may layfrom 180 to 350 in a mass in 7 to 11 rows. The eggs hatch after one tothree days. An egg mass of a Culex mosquito is shown in fig. 48. Anopheles crucians Wiedemann has an elongate fusiform egg(fig. 49c) slightly more tapered toward one end, both ends dorsal surface is granular, the ventral surface coarsely hexagonallyreticulate. The floats occupy about half the sides in top view, and arcseparated at the middle by nearly one-third the diameter of the egg. 268 SANITARY ENTOMOLOGY These eggs are laid singly, a small number at a time, upon the surface ofthe water. Anopheles punctipennis Say (fig. 49a) has an elongate fusiform Gggireticulate ventricallj^, finely granular dorsally. The floats are large,extending nearly to the apices, closely approximated medianly on thedorsal surface, arcuately produced at the sides to the apical fourths,. Fig. 48.—Eggs and larvae of Culex. Enlarged. (Howard.) From U. S. Dept. Agr., Farmers Bull. 155, fig. 5. widely separated on the ventral surface, and showing only on middlethird of sides. The eggs are laid singly or in small groups upon thesurface of the water. Anopheles quadrimaculatus egg is shown in fig. 49b. THE LARVAE AND THEIR HABITS All mosquito larvas are aquatic. By far the most of the larvae occurin small deposits of water, although certain species occur in large bodies
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectbenefic, bookyear1921
