a1 Department of Marine Biology, University of Liverpool, Port Erin, Isle of Man
Some understanding of the mechanisms involved in the development and maintenance of forests of Laminaria hyperborea (Gunn.) Fosl. can be gained from the analysis of populations under different conditions. The main variable is depth and unfortunately the available depth range of suitable substrata in the Isle of Man is limited. For this reason two visits were made to western Scotland and the Outer Hebrides, in 1970 and 1976. This paper, which is intended as the last in this series, reports on results obtained rom there and from certain sites in the Isle of Man.