»IM l'lioto. H. J. b.mslniry Sun-cracked Mud with the Alga Microcoleus chthonoplastcs\ Seedlings of Sucsda maritima arising in the cracks Plate XV Photo, supplied by Dr. S. M. Baker Mud Slope covered with Fucus limicola; Aster and Salicornia are beginning to settle (Mersea Island, Essex) mk