Pole cell

In early Drosophila development, the first 13 passes through mitosis are nuclear divisions (karyokinesis) without cytokinesis, resulting in a multinucleate cell (generally referred to as a syncytium, but strictly a coenocyte). The first mononucleate cells are created at the posterior pole, where the polar granules are tethered. These cells are called pole cells, and they will form the fly's germ line.

...
Wikipedia