How does multicellularity evolve? Scientists who study a family of green algae that includes unicellular Chlamydomonas and multicellular Volvox are beginning to find answers to this question. Before ...

IN this third memoir M. Janet approaches the problem of the ontogenesis of the Volvox blastea (ccenobium). He confines himself to the methods of cell bipartition, but in later works he proposes to ...