Karyological analysis of Acupalpus /Stenolophus/ teutonus /schrank/ and Pogonus persicus,Chaud. /coleoptera, carabidae/

: Retrovirus-like particles were detected by the negative staining method in supernatants of lymph node and spleen cell suspensions prepared from Sprague-Dawley rats with spontaneous acute lymphoblastic leukaemia (ALL). Similar particles were found in supernatants of cell suspensions from a lymphoma that developed after inoculation of lymph node and spleen cell suspension prepared from animals with spontaneous ALL into the subcutis of Sprague-Dawley recipients. On ultrathin sections, budding forms of the virus particles were seen as a dot at the periphery of neoplastically transformed cells.