Embryonic Development

In embryos of a given species, one or both methods may be seen in different segments. For example, internal splitting of the somites occurs in all segments of embryos of Phasmida, most hemipteroid insects, and most endopterygotes, and in the abdominal segments of Locusta embryos. Median folding is the method used in all segments in embryos of Odonata, Dictyoptera, and Mallophaga, and in the gnathal and thoracic segments of those of Locusta, and some Coleoptera, Lepidoptera, and Megaloptera. In exopterygote embryos, all somites usually develop a central cavity, though this may be only temporary. Among endopterygotes, members of more primitive orders retain a full complement of somites in their embryos and the latter usually develop a coelom. In embryos of some species, however, cavities may not form, and somite formation may be suppressed in the head segments. In embryos of Diptera and Hymenoptera, no distinct head somites appear, and in those of some Muscomorpha and Apocrita, somite formation is entirely suppressed, so that mesodermal derivatives are produced directly from a single midventral mass.

Beekeeping for Beginners

Beekeeping for Beginners

The information in this book is useful to anyone wanting to start beekeeping as a hobby or a business. It was written for beginners. Those who have never looked into beekeeping, may not understand the meaning of the terminology used by people in the industry. We have tried to overcome the problem by giving explanations. We want you to be able to use this book as a guide in to beekeeping.

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