NUCLEAR-CYTOPLASMIC EXCHANGE DURING SPERMATOGENESIS OF GRYLLOTALPA AFRICANA L (ORTHOPTERA, GRYLLIDAE)

During spermatogenesis of Gryllotalpa africana nuclear-cytoplasmic exc hange takes place both in spermatocytes and in spermatids. In spermato cytes I emission of nuclear material begins before onset of meiosis wi th small amounts of electron-dense material which is distributed as nu age between mitochondria. During meiosis electron-dense material aroun d the nuclear envelope increases continuously reaching its culmination in late stages. While nuage between mitochondria disappears the emitt ed material aggregates to large granules which are transferred to sper matids. In young spermatids the granules are associated with stacks of parallel endoplasmic cisternae, between which their material seems to be distributed. A second type of electron-dense material, the chromat oid body, appears connected with a many pores containing area of the e nvelope at the apical pole of the nucleus. It is intermingled with ele ments of endoplasmic reticulum and always in close association with a lysosomal complex. After disconnection from the nucleus the chromatoid body, together with the lysosomal complex, moves to the caudal pole o f the nucleus where it finally disappears. Thus, in Gryllotalpa, there is a clear temporal and spatial separation which makes it possible to follow origin and later fate of granule and chromatoid body independe ntly from each other.