. Injurious and useful insects; an introduction to the study of economic entomology. Insects; Beneficial insects; Insect pests. EXTERNAL PARTS OF A COCKROACH 9 pair of well-developed wings in the male. When not in use, they are folded up fanwise, beneath the wing-covers. The female has no wings, but a reticulated pattern on the outer margin of the metathoracic tergum represents a pair of wings which have disappeared. The wing-covers of the male, though stiff in the cockroach, represent a pair of true wings, which are membranous and useful for flight in many insects. The thoracic sterna are muc
. Injurious and useful insects; an introduction to the study of economic entomology. Insects; Beneficial insects; Insect pests. EXTERNAL PARTS OF A COCKROACH 9 pair of well-developed wings in the male. When not in use, they are folded up fanwise, beneath the wing-covers. The female has no wings, but a reticulated pattern on the outer margin of the metathoracic tergum represents a pair of wings which have disappeared. The wing-covers of the male, though stiff in the cockroach, represent a pair of true wings, which are membranous and useful for flight in many insects. The thoracic sterna are much encroached upon by the bases of the legs, and cannot well be seen without a lens. Three pairs of legs are carried on the thorax, one pair to each segment. They regularly increase in size from the first to the third, but hardly differ otherwise. Each is divided into the five parts usual in insects. The coxa (haunch) or basal joint is broad and flattened. The troclianter is a small piece connecting the coxa with the femur (thigh), the elongate third joint of the Fig. 6.—Profile of male and female cockroach. The tibia (shin) succeeds the femur, and is of about the same length. Then comes a five-jointed tarsus (foot), which ends in a pair of claws. The abdominal segments consist of dorsal plates (terga) and ventral plates (sterna). The first abdominal segment has only a vestige of a sternum. The hindmost plates are somewhat irregular, and the arrangement is different in the two sexes. A pair of jointed cerci project from the end of the abdomen in both sexes, and in the male a pair of slender styles can be seen between the cerci. In the abdomen of the female eight terga (1-7, and 10) are externally visible. Two more (8, 9) are. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Miall, Louis Compton, 1842-.
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectinsects, bookyear1902
