Sand tubes created by marine worms are glued together with mucus.

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"The colonies built by Sabellaria worms on seashore rocks look like very untidy honeycombs. The worms construct tubes of sand grains stuck together with mucus.

"This surface of a colony of Sabellaria tubeworms (above and left) looks like an untidy and somewhat squashed honeycomb. Sabellaria worms are marine worms about 30 mm long which build tubes by cementing together particles of sand and rock. When not covered by the tide, the worms remain hidden inside the tube, but once covered with water, they protrude from its mouth and extend their tentacles to feed. Sabellaria colonies can form extensive reefs made up of millions of tubes." (Foy and Oxford Scientific Films 1982:32-33)

Book
The grand design: Form and colour in animalsBLA Publishing Limited for J.M.Dent & Sons Ltd, Aldine House, LondonAugust 4, 1983
Sally Foy

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