Spurge flower

These very characteristicly reduced flowers are typical for the plant family of the spurgelike plants (Euphorbiaceae), which contains more than 8000 species. Among these trees, shrubs, climbers, very bizarre succulents, rosette plants and tuft trees. In central Europe there are only some few field weeds, as the one on the picture, a very common weed. Some species are popular indoor plants.

I think I took the picture in may 2000 at the margin of a fallow field near Bonn (germany), but I'm not sure.