278 tubules that enter the gut via two lateral ducts. Only two tubules occur in some species. The nervous system is somewhat concentrated. In the most primitive condition three thoracic and five abdominal ganglia are found. In the majority of Lepidoptera, however, there are two thoracic and four abdominal centers. In most male Lepidoptera the four testis follicles on each side are intimately fused to form a single median gonad, though the vas deferens on each side remains separate and posteriorly becomes dilated to form a seminal vesicle before opening into the ductus ejaculatorius duplex. The latter also receives one, rarely two, accessory glands. Sperm is stored in both the seminal vesicles and the duplexes, the latter opening into the common ejaculatory duct (simplex). In most species four polytrophic ovarioles occur in each ovary, which joins the common oviduct via a short lateral tube. Various accessory glands open into the oviduct. During mating, sperm (transferred in a spermatophore) is deposited in the bursa copulatrix; in monotrysian and exoporian forms, it remains here, but in Ditrysia the sperm then moves via the sperm duct to the spermatheca where it is stored till required.

Larva and Pupa. Larvae (caterpillars) are eruciform, and the three primary body divisions are easily recognizable. The head is heavily sclerotized and bears strong, biting mouthparts, six ocelli in most species, and short, three-segmented antennae. In Glossatathe prementum carries a median spinneret that receives the ducts of the silk (modified salivary) glands. Three pairs of thoracic legs and, in most species, five pairs of abdominal prolegs occur; the latter are located on segments 3-6 and on segment 10. At the opposite extreme, many leaf-mining larvae are apodous. Larvae are usually equipped with some method for protecting themselves from would-be predators. They may be colored either procryptically or aposematically; they may build shelters in which to hide, or they may possess a variety of repugnatory devices, such as glands that produce an obnoxious fluid, or long irritating hairs that invest the body. The pupae of most Lepidoptera are adecticous and obtect. In lower members of the order, however, they are decticous and exarate.

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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