Elementary entomology elementaryentomo00sand Year: [c1912] ANATOMY OF INSECTS - - INTERNAL 7 The work performed by the muscles of insects appears prodigious compared with that done by higher animals. Thus the weakest insect can pull over twenty times its weight. A house-fly can carry a match, to equal which a man would need to carry a timber thirty-five feet long and as large around as his body. An earwig can lift twelve times its weight, and a honey-bee, in flight, carries four fifths of its weight. A small insect is relatively stronger than a large one, and the relative strength of insects
Elementary entomology elementaryentomo00sand Year: [c1912] ANATOMY OF INSECTS - - INTERNAL 7 The work performed by the muscles of insects appears prodigious compared with that done by higher animals. Thus the weakest insect can pull over twenty times its weight. A house-fly can carry a match, to equal which a man would need to carry a timber thirty-five feet long and as large around as his body. An earwig can lift twelve times its weight, and a honey-bee, in flight, carries four fifths of its weight. A small insect is relatively stronger than a large one, and the relative strength of insects is largely accounted for by their small size. This is due to the fact that the weight increases as the cube of a single dimension, while the strength of a muscle increases as the square of its diameter. The endurance and rapidity of muscular action of insects is no less mar- velous. By determin- ing the pitch of the note made by the wing vibrations of a gnat, physicists have shown that its wings may move as much as fifteen thou- sand times per minute. The prolonged vibra- tion of the honey-bee's wings is another instance of remarkable muscular endurance. Nervous system. The nervous system consists of a series of small white ganglia which are connected by a double nerve cord lying along the bottom of the body cavity. In the larvae there is usually one ganglion to each segment, but in the adult insects the ganglia are often fused together, those of the thorax and an- terior abdominal segments having grown together, as well as those toward the tip of the abdomen. In the head the ganglia have grown together to form the brain, which lies just above the esoph- agus and which is connected with the subesophageal ganglion by a double nerve cord, one commissure of wThich passes on either side
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