. Outlines of zoology. Fig. 174.—Ventral aspect of male cockroach with the wings imaginary median line has been inserted. A,^ antennse ; E., eye ; ^ prothorax ; f^, first pair of wings ;W^^ second pair of wings; C, cercus; style; Co,, coxa;Tr., trochanter; F., femur; TV., tibia; Ta., tarsus. Skin.—There is an external chitinous cuticle and asubjacent cellular layer—the epidermis or hypodermis—from which the cuticle is formed. The newly hatchedcockroaches are white, the adults are dark brown. Moulting, which involves a casting of the cuticle, of theinternal lining of the tr
. Outlines of zoology. Fig. 174.—Ventral aspect of male cockroach with the wings imaginary median line has been inserted. A,^ antennse ; E., eye ; ^ prothorax ; f^, first pair of wings ;W^^ second pair of wings; C, cercus; style; Co,, coxa;Tr., trochanter; F., femur; TV., tibia; Ta., tarsus. Skin.—There is an external chitinous cuticle and asubjacent cellular layer—the epidermis or hypodermis—from which the cuticle is formed. The newly hatchedcockroaches are white, the adults are dark brown. Moulting, which involves a casting of the cuticle, of theinternal lining of the tracheae, etc., occurs some seven timesbefore the cockroach attains in its fifth year to maturity. The muscles which move the appendages, and produce COCKROACH. 329. Fig. 175.—Leg of cockroach. ?., Broad expanded coxa; ir.^ troch-anter ;_/I, femur; ii.^ tibia; ia.^ six-jointed tarsus with terminal clawsand adhesive cushions. the abdominal movements essential to respiration, aremarkedly cross striped. Theyare in many cases attachedto special tendons, whicharise as cuticular invagina-tions, and are lost and re-placed at each moult. Nervous system.—A pairof supra-oesophageal or cere-bral ganglia lie united in thehead. As a brain they receiveimpressions by antennary andoptic nerves. By means of apaired commissure surround-ing the gullet, they are con-nected with a double ventral chain of ten ganglia. Of these, the first or sub-oesopha-geal pair are large, and give off nerves to the mouth-parts, etc.; from each of theganglia of the thoraxand the abdomennerves are given offto adjacent are three pairsof ganglia in thethorax, and six in theabdomen, of which thelast is the largest,From the oesophagealcommissures visceralnerves are given o
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Keywords: ., bookcentury1900, bookdecade1910, bookidcu3192, booksubjectzoology
