Structure

chapter 7 Most members of this order are remarkable for their close resemblance to the plants on which they are normally found (Figure 7.15). The body, which in some species may exceed 30 cm in length, is commonly elongate, wingless, or brachypterous and resembles a twig. In those species that retain wings the body may be dorsoventrally flattened and sculptured so as to resemble a leaf or a group of leaves.

The prognathous head bears a pair of antennae that may beshort to very long. Compound eyes are always present, but ocelli are found only in some of the winged species, when they may be confined to males. In accord with the phytophagous habit, the mouthparts are of a generalized mandibulate form. The prothorax is small, while the mesothorax and metathorax are elongate with the latter usually firmly connected to the first abdominal segment. Wings may be present or absent, and all intermediate conditions of brachyptery are known. When wings are present they are typically fully developed in males but reduced in females. The fore wings take the form of tegmina, which in many species are much shorter than the hind wings. In leaflike species the venation is much modified to mimic the veins of a leaf. All legs are similar, with small, widely separated coxae and, in the leaflike forms, broadly flattened tibiae and femora. Eleven abdominal segments are present, though the 11th is represented only by the epiproct, paired paraprocts, and unsegmented cerci. In males the terminal abdominal segments and the aedeagus are of varied form; in some species the cerci are modified as claspers; and a sclerotized, prong-shaped process, the vomer, used in copulation, occurs in some groups. The ovipositor, which comprises three pairs of small valves, is covered by the operculum, a keel-shaped structure formed from the eighth sternum.

The gut is straight and comprises a large crop whose posterior part functions as a gizzard, a long midgut that bears numerous external papillae over its posterior part, and a short hindgut. Numerous Malpighian tubules, arranged in two groups, enter the gut via a common duct. The central nervous system is primitive and includes three thoracic and seven abdominal ganglia. The male reproductive system consists of a pair of tubular testes and short vasa deferentia that open together with various accessory glands into the ejaculatory

FIGURE 7.15. Phasmida. (A) A leaf insect, Phyllium sp.; and (B) a stick insect, Carausius morosus. [A, from P.-P. Grassé (ed.), 1949, Traite de Zoologie, Vol. IX. By permission of Masson, Paris. B, from H. Ling Roth, 1916, Observations on the growth and habits of the stick insect, Carausius morosus Br., Trans. Entomol. Soc. Lond. 1916:345-386. By permission of the Royal Entomological Society.]

FIGURE 7.15. Phasmida. (A) A leaf insect, Phyllium sp.; and (B) a stick insect, Carausius morosus. [A, from P.-P. Grassé (ed.), 1949, Traite de Zoologie, Vol. IX. By permission of Masson, Paris. B, from H. Ling Roth, 1916, Observations on the growth and habits of the stick insect, Carausius morosus Br., Trans. Entomol. Soc. Lond. 1916:345-386. By permission of the Royal Entomological Society.]

duct. In females several panoistic ovarioles lie alongside the lateral oviducts. One or two spermathecae and a pair of accessory glands open into the dorsally placed bursa copulatrix near its junction with the common oviduct. Paired prothoracic repugnatory glands, opening to the exterior in front of the fore coxae, occur in some species, for example, the North American two-striped walking stick (Anisomorpha buprestoides).

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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