“…Midgut development has been studied in several lepidopterans including Tineola (Lothmar 1942), Agíais (Henson 1931, Bombyx (Waku & Sumimoto 1971, 1974, Hyalophora (Judy & Gilbert 1970) and Manduca; the more recent contributions were reviewed (with emphasis on Manduca) by Baldwin et al (1996). Near the beginning of a moult the small regenerative (or 'stem') cells proliferate and eventually outnumber the differentiated cells.…”