ON THE ORIENTATION OF SEA FANS (GENUS GORGONIA)

摘要: Sea fans (Gorgonia ventalina and G. flabelluin) grow in patches at depths of 2 to 10 m on the seaward reefs Florida Keys. The sea any particular patch appear have a preferred orientation their fan “?�blades.” ThA©odorand Denizot ( 1965 ) noted this phenomenon concluded from parallel orien tation algae gorgonians that all fan-shaped sessile organ isms is perpendicular wave motion it may result solely hydro dynamic phenomena. We asked questions, “?�To what extent do show ?“ “?�What can be inferred morphology habitat concerning mechanism brings about METHODS worked several coral reef sites upper Keys over July August, 1966, put more than 25 man-hours making observations photo graphs while using self-contained underwater breathing apparatus. spent least one fifth time diving through twilight hours into darkness. exposed twenty-four 50-foot rolls Super 8 mm movie film Kodak M-6 camera with close-up lenses record aid further study activities soft stony corals. For measurement blades points compass, waterproof compass was mounted center 12” square white plastic board. Holding board horizontally we then placed side flat against blade made pencil mark north arrow. measured maximum height breadth ±0.5 cm 30 rule recorded these figures next mark. data for every each studied. surveyed following places: