甜菜夜蛾胚胎发育的研究(Ⅲ)——呼吸、消化、神经、生殖系统的发育

详细研究了甜菜夜蛾Spodoptera exigua(Huebner)]在胚胎发育中呼吸、消化、神经、生殖系统的发育过程及特点。呼吸系统由中、后胸及1～8腹节外胚层内陷而成，到发育后期，中胸气门移至前胸，后胸气门退化；前肠、后肠分别来自原口陷和原肛陷，前肠分化为食道、嗉囊和前胃，后肠分化为前后肠和直肠，中肠来自中肠前基和中肠后基两群内胚层细咆，6条马氏管的末端插入直肠后端的肠壁内形成“隐肾”；腹神经索呈梯状，口道神经系出现额神经节和嗉囊神经节两大细胞群；原始生殖细胞来自极细胞，分两团移至胚胎腹部侧背面，被中胚层细胞包裹，形成生殖脊。

Studies on the Embryonic Development of Spodoptera exigua (Hübner) (Ⅲ)--The Development of Respiratory, Digestive, Nervous and Reproductive System

The development of respiratory,digestive,nervous and reproductive system during the embryonic development of Spodoptera exigua(Hübner)was surveyed.The ectodermal cells of mesothorax,meta thorax and 1 to 8 abdomen got in to form the respira tory system.The spiracles at mesothorax moved to prothorax and spiracles at meta thorax disapp eared in the later development.The foregu tand hindgu tderived resp ectively from the stomodaeum and proctodaeum.The foregut would be differentia ted in to oesop hagus,crop and proven triculus while the hindgutin to ileocolon and rectum.The midgut came froman terior mesen teron rudiments and posterior mesen teronrudiments.Six Malpighian tubes formed cry tonep hridiel by putting theirtube ends in to the rectum wall.The ventral nerve cord looked like a ladder.The stomodaeal nervous system comprised frontal gang lion anding luvial gang lion.Primordial germ cells came from pole cells and moved in two masses to the laterodo rsalab-domen of embryo,and then were enveloped by mesoderm to form germinal ridge.