Some remarks on the cytology of Oenothera

Of late the cytology of the genus Oenothera has been repeatedly discussed. Originally the question whether there occurs parasynapsis or telosynapsis in this genus formed the main point of these discussions. Most investigators described Oenothera as a specimen of telosynapsis (Geerts, Gates, Davis, Cleland, Hakansson, etc.1), although from the beginning the opinion of parasynapsis has been maintained by a few others. As early as 1910, Stomps2) held the latter opinion regarding Oenothera, this being the result of a comparison between the corresponding stages in Spinacia and the plant under discussion. In later years it was especially B o e d ij n 3) who advocated parasynapsis. The latter studied not so much the praesynaptic stages, but pachynema and diakinesis.