During the past decade there has been so fundamental an advance in our knowledge of the reproductive processes and life history of the Phaeophyceae, that it seems to exceed in importance the change in viewpoint regarding any other group of plants during the same period. The work which must so largely overturn our ideas has mainly been done by European algologists, and has not been followed up in this country by any confirmatory studies; indeed, it seems to be little known. As each succeeding paper, and several from independent sources have now appeared, confirms the critical points of the others, it seems desirable at this time to review the situation and to indicate the necessary changes in the classification of the group. To date the only review in English of the studies in question is a short one by LEWIS (ii), written at an early stage. Three have appeared in France, one by CONSTANTIN (I), and two by PECHOUTRE (i6, i7), these latter of special value.