Embryology of insects and myriapods; Embryology of insects and myriapods; the developmental history of insects, centipedes, and millepedes from egg desposition [!] to hatching embryologyofinse00joha Year: 1941 Fig. 113.—Lihellula. A-C, longitudinal section, successive stages. {nu) Nucleus. slightly in shape and size, but their development is similar in ah respects. They are laid in the same localities, and the actions of the female during oviposition are similar. The females of all three species lay the eggs as they fly in circles over the water and dip their abdomens momentarily to wash o
Embryology of insects and myriapods; Embryology of insects and myriapods; the developmental history of insects, centipedes, and millepedes from egg desposition [!] to hatching embryologyofinse00joha Year: 1941 Fig. 113.—Lihellula. A-C, longitudinal section, successive stages. {nu) Nucleus. slightly in shape and size, but their development is similar in ah respects. They are laid in the same localities, and the actions of the female during oviposition are similar. The females of all three species lay the eggs as they fly in circles over the water and dip their abdomens momentarily to wash off the egg mass being extruded from the oviduct. The eggs of the mass sink to the bottom singly, and each soon produces a viscid substance which causes the egg to stick to anything it touches. Sometimes the eggs drift into a clump and become deeply imbedded in a mass of jelly. The eggs of Plathemis lydia are ovoid in form but are pointed at both ends. There is no difference between dorsal and ventral sides. The eggs of Lihellula 'pulchella and Erythemis simplicicollis are approximately the same size but are smaller than those of Plathemis and are not so pointed. The shell of all three is tough and creamy white; the yolk is very dense; and the globules often appear cuboidal or hexagonal in cross sec- tion. The peripheral cytoplasm, which is very thin, adheres so closely to the chorion that a thin vitelline membrane reported in other species was not seen. Maturation and fertilization were not observed. In the egg of Lihellula, three hours old, a nucleus is present at the center of the yolk,
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