Normal and Induced Degeneration of Abdominal Muscles during Metamorphosis in the Lepidoptera

摘要: Certain segmental units of the three main longitudinal muscle-bands in abdomen larva Galleria, Platysamia, Telea, Antheraea , and Samia (Philosamia ) do not degenerate during histolytic phase prepupa early pupa. In 3rd abdominal segment amount muscle that persists is variable; 4th, 5th, 6th segments, invariable. Apart from single pairs transverse muscles 2nd segments those gut heart there are no other Vestiges degenerated often found The which survive transformation pupa into adult first 2 days life. Experiments were made on larvae, prepupae, pupae, adults attempts to influence muscle-degeneration muscle-persistence. Extirpation ganglia or severance nerves larvae prepupae Galleria caused normally persistent pupation. Controls dissected before pupation revealed degeneration denervated muscles. saturniids denervation also resulted atrophy but only after a much longer period, matter several weeks instead days. Muscles may be affected by extirpation preceding their own segment. Previous workers have shown growth new dependent central nervous system. This so case sheets fine muscle-fibres lying under epidermis adult. They develop absence innervation. Operations had effect included adult, beheading bleeding, corpora allata plus cardiaca, ligations, pupal gonads, isolation abdomens. Substitution blood diapausing pupae saline for isolated abdomens was effective slowing process muscle-degeneration. result shows composition importance histolysis previous work physiology insect briefly reviewed. system as described this paper discussed related similar findings arthropods vertebrates.