270 larval or adult instar, rarely the egg stage, is characteristic of many species. Some larvae are free-living and construct a shelter only at pupation; others build a non-portable silken web (fixed-retreat species), which, in addition to providing them with protection, also serves to trap food. Most larvae, however, construct a portable case whose shape and the nature of the materials incorporated into it are varied but characteristic for a particular family or even genus. The case has a silken lining to which other materials both organic and inorganic are stuck. Broadly speaking, the free-living forms are predators or feed on dead animal materials, the fixed-retreat builders are filter feeders or gather organic matter trapped in their web, and the portable-case bearers may be shredders, grazers and scrapers, or piercers (obtaining their food by sucking fluids from living plants).

Prior to pupation, larvae of most case-building species attach their case to the substrate and close off each end with a perforated silken wall which allows the continued passage of water through the case for gas exchange. Some species close the anterior end with plant materials held together by silk, and a few species build an entirely new case. In most fixed-retreat species mature larvae abandon their web and construct a separate pupal enclosure similar to that of case builders; others pupate within the web. Mature larvae of many free-living species first construct a rough, dome-shaped structure that they attach to the substrate. Within this they build a discrete smooth and imperforate cocoon. Water cannot flow through the cocoon and the gas exchange occurs solely by diffusion across the fluid-filled cavity (Wiggins and Wichard, 1989). The pharate adult (often incorrectly referred to as the "pupa") (see Chapter 21, Section 3.3.3) bites its way out of the case or cocoon using the pupal mandibles and crawls or swims to a suitable emergence site. Molting takes place at the water surface and adults can fly immediately after their wings are expanded.

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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