All brown algae is part of the Class Phaeophyta and the Phylum Ochrophyta. Brown algae is the largest group of algae, and they grow in shallow waters and on rocky shores. They are multicellular and can reproduce sexually and asexually. They are generally bush-like with blades. They contain a pigment, "Fucoxanthin" which gives brown algae different shades of brown-yellow, green-brown to even dark brown.
Sergassum fluitans
Sargassum fluitans are pelagic macro-algae that provides shelter for marine life. They have pneumatocysts that providing the necessary buoyancy.
Their size can range between 0.5 to 1.5 feet. They are not anchored to the bottom of the sea floor; thus, as a free-floater, is controlled by the flow of the water. They are washed up onto the shores of the Caribbean, Bahamas and South Florida around the spring through summer seasons.
Padina jamaicensis
Padina jamaicensis is also known as White Scroll Algae.
This algae is part of the genus Padina which is known for the having a leaf-like structure. They have blades that split and are irregularly branched.
They are heavily fed on by fish; thus, they produce thinner strands to remove the fish and then form their blade like structure.
They can be found attached to rocks in shallow reef flats in the Caribbean.
Florent Charpin. "White Scroll Alga." http://reefguide.org/carib/whitescrollalga.html.
Gerardo Aizpuru. "White Scroll Algas." 2013. http://www.projectnoah.org/spottings/10490063.
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Seaweeds of Alaska. "Seaweed: Ochrophyta." http://www.seaweedsofalaska.com/seaweed.asp?phylum=Ochrophyta.
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