Marine Animal Encyclopedia
Cotton's Seaweed Kappaphycus cottonii
Formerly called Eucheuma cottonii, Cotton's seaweed is a much-branched, cylindrical red seaweed that is farmed extensively in the Philippines for extraction of carrageenan, a gelling agent similar to agar (see Seaweed Jelly). In the wild, it grows attached to rocks or lies loose in sheltered places. Like some other red seaweeds, Cotton's seaweed's fronds are often shades of green and brown rather than red.