Abstract

Spermatogenesis in cysts isolated from testes of Drosophila and morphogenesis of male germ cell mitochondria were observed in vitro and compared with their first description in the literature. Since Drosophila started to be used for laboratory research only at the beginning of the 20th century, publications dealing with other insects have been consulted for earlier periods. Formerly, results were usually obtained from squashed preparations. This technique causes many artifacts and only occasionally can intact cysts be observed. It was only after tissue culture technique and microscopes improved that in vitro observation of differentiating cysts became possible. However, thanks to acute observational skills and careful reasoning, former researchers already had a correct picture of the early development of male germ cell mitochondria. Modern high resolution microscopy confirmed their results