DNA Content and Synthesis in Several Tissues and Variation of Moulting Hormone-Level in Gryllus bimaculatus DEG (Ensifera, Insecta)
The mode of growth of several tissues in Gryllus bimaculatus was investigated during postembryonic development by cytophotometric methods. In contrast to the situation in holo- metabolous insects, the tissues growing by endomitosis reach only moderate levels of polyploidy. In this case the growth of tissues is achieved by mitotic divisions of small cells with subsequent polyploidization. The time courses of DNA synthesis were measured within the 3rd and, for comparison, the 8th larval instar by incorporation of labelled thymidine followed by autoradiography. Hemocytes, cells of the regeneration crypts of the midgut, gonads and nervous tissue showed a continuous incorporation rate; by contra…