Ojt

FIGURE 3.22. Structure of the coxa. (A) Lateral view; and (B) coxa with a well-developed meron. [From R. E. Snodgrass, Principles of Insect Morphology. Copyright 1935 by McGraw-Hill, Inc. Used with permission of McGraw-Hill Book Company.]

Leg Modifications. The functions for which the legs have become modified include jumping, swimming, grasping, digging, sound production, and cleaning.

In Orthoptera and a few Coleoptera (e.g., flea beetles) the femur on the hindleg is greatly enlarged to accommodate the extensor muscles of the tibia used in jumping. In swimming insects, the tibia and tarsus of the hindlegs (occasionally also the middle legs) are flattened and bear rigid hairs around the periphery (Figure 3.24A). Legs modified for grasping are found in predaceous insects such as the mantis and giant water bug, in ectoparasitic lice, and in males of various species where they are used for hanging onto the female during mating. In the mantis, the tibia and femur of the foreleg are equipped with spines and operate together as pincers (Figure 3.24B). The foreleg of a louse is short and thick and has at its tip a single, large tarsal claw that folds back against the tibial process (Figure 3.24C). Suctorial pads have been developed on the fore limbs in males of many beetle species. In Dytiscus, for example, the first three tarsomeres are flattened and possess large numbers of cuticular arolium

'tendon' of depressor muscle of pretarsus arolium

FIGURE 3.23. Distal part of a leg showing the arolium and claws. [From R. E. Snodgrass, Principles of Insect Morphology. Copyright 1935 by McGraw-Hill, Inc. Used with permission of McGraw-Hill Book Company.]

'tendon' of depressor muscle of pretarsus

FIGURE 3.24. Leg modifications. (A) Hindleg of Gyrinus (swimming); (B) foreleg of a mantis (grasping prey); (C) foreleg of a louse (attachment to host); (D) foreleg of Dytiscus (holding onto female); and (E) foreleg of a mole cricket (digging). [A, after L. C. Miall, 1922, The Natural History of Aquatic Insects, published by Macmillan Ltd. B, D, E, after J. W. Folsom, 1906, Entomology: With Special Reference to Its Biological and Economic Aspects.]

FIGURE 3.24. Leg modifications. (A) Hindleg of Gyrinus (swimming); (B) foreleg of a mantis (grasping prey); (C) foreleg of a louse (attachment to host); (D) foreleg of Dytiscus (holding onto female); and (E) foreleg of a mole cricket (digging). [A, after L. C. Miall, 1922, The Natural History of Aquatic Insects, published by Macmillan Ltd. B, D, E, after J. W. Folsom, 1906, Entomology: With Special Reference to Its Biological and Economic Aspects.]

cups, two of which are extremely enlarged (Figure 3.24D). The forelegs of soil-dwelling insects such as the mole cricket (Figure 3.24E), cicadas, and various beetles are modified for digging. The legs are large, heavily sclerotized, and possess stout claws. The tarsomeres are reduced in number or may disappear entirely in some forms. In many Orthoptera sounds are produced when the hind femora, which have a row of cuticular pegs on their inner surface, are rubbed against ridged veins on the fore wing. Modifications to the forelegs for cleaning purposes are found in many insects. In certain Coleoptera and Hymenoptera, for example, the honey bee (Figure 3.25A), a notch lined with hairs occurs on the metatarsus

FIGURE 3.25. Leg modifications in the worker honey bee. (A) Foreleg showing the cleaning notch, (B) outer surface of hindleg showing the pollen basket, and (C) inner surface of hind tarsus and tip of hind tibia showing rake and pollen press. [After R. E. Snodgrass, 1925. Anatomy and Physiology of the Honey bee, McGraw-Hill Book Company.]

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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