We cannot be certain that Gonium, pandonina, Eudonna, and Pleodorina represent stages in the evolution of multicellular Volvox from unicellular chlamydomonas.
我们不能肯定盘藻、实球藻、空球藻和杂球藻代表从单细胞衣藻到多细胞因藻的各进化阶段。
2
It was difficult to distinguish oogonium from spermatogonium according to the shape and size of gonium under light microscope.