A text-book of entomology, including the anatomy, physiology, embryology and metamorphoses of insects, for use in agricultural and technical schools and colleges as well as by the working entomologist . re, retaining the simple annular shape of embryonic life, and from their generalizednature their number can bereadily distinguished (Fig. 176).The tergal and sternal pieces ofeach segment are of nearly thesame size, the tergal often over-lapping the sternal (though in the Coleoptera the sternites are larger than the tergites), while there are no pleura! pieces, the lateral region being membrano
A text-book of entomology, including the anatomy, physiology, embryology and metamorphoses of insects, for use in agricultural and technical schools and colleges as well as by the working entomologist . re, retaining the simple annular shape of embryonic life, and from their generalizednature their number can bereadily distinguished (Fig. 176).The tergal and sternal pieces ofeach segment are of nearly thesame size, the tergal often over-lapping the sternal (though in the Coleoptera the sternites are larger than the tergites), while there are no pleura! pieces, the lateral region being membranous when visible and bearing the stigmata (Fig. 177, L). In the terminal segments beyond the genital outlet, however, there is a reduction in and loss of segments, espe-cially in the adults of the metabolous orders, notably the Panorpidse (Fig. 177), Diptera, and aculeate Hymenoptera; in the Chrysididae only three or four being usually visible, the distal segments being reduced and telescoped inward. The typical number of abdominal segments (uromeres), that occurring in each order of insects, is ten; and in certain families of Orthoptera, eleven. In the embryos, however, of the most general-.
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Keywords: ., bookcentury1800, bookdecade1890, bookpublishe, booksubjectinsects
