. The biology of insects. Insects -- Biology. MOVEMENT 51 Abd. of coxa sclerites, which are thus capable of movement in relation to each other (Fig. 17). The segment of an insect's leg next the body is the conical or subconical haunch (coxa), the broad base of which adjoins the sternal region of its segment while it tapers distally to its junction with the small sickle-shaped trochanter which is succeeded by the long stout thigh or femur. In some in- sects, cockroaches for example, the cuticle of the haunch is partly transparent so that the strong muscles which, by their contraction, move the
. The biology of insects. Insects -- Biology. MOVEMENT 51 Abd. of coxa sclerites, which are thus capable of movement in relation to each other (Fig. 17). The segment of an insect's leg next the body is the conical or subconical haunch (coxa), the broad base of which adjoins the sternal region of its segment while it tapers distally to its junction with the small sickle-shaped trochanter which is succeeded by the long stout thigh or femur. In some in- sects, cockroaches for example, the cuticle of the haunch is partly transparent so that the strong muscles which, by their contraction, move the leg as a whole can be seen through it, their white colour contrasting markedly with the general brown hue of the exoskeleton. The leg-muscles in the cock- roach are described by Miall and Denny (1886). From the dorsal region of the thorax on either side muscles pass to the inner and outer edges of each haunch ; these are respectively the adductor and abductor coxae, as by contraction of the former the leg is drawn in towards the axis of the body, while by con- traction of the latter it is moved outwards. A very strong muscle with its basal attachment (origin) also on the thoracic skeleton traverses the haunch, its fibres converging to their distal attach- ment (insertion) by means of a tendon on the inner (convex) edge of the trochanter. This is the muscle whose contraction straightens the thigh in relation to the. €xt. lib. R«tr. tan. Fig. 17.—Left intermediate Leg of Cockroach (Blatta orien- talis), showing segments and muscles, c, coxa; tr, tro- chanter ; /, femur or thigh ; ti, tibia or shin ; ta, tarsus or foot. Muscles: Add, adductor; Abd, abductor ; Ext, extensor ; Fl, flexor : Retr, retractor. X3. After L. C. Miall and A Denny, The Cockroach^ 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 work.
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Keywords: ., bookcentury1900, bookdecade1920, bookpublishernewyorkthemacmilla
