tubicola

from The Century Dictionary.

• In paleontology, a group of indeterminate value comprising all the fossil tube-dwelling worms found in geological formations. These fossil worm-tubes are variously shaped, straight, curved, spirally coiled, and turreted, and are made up of cemented sand or mud particles or of membranous, leathery, or calcareous matter secreted by the worms. They are found in rocks of all ages, and the best known among them are included in the genera Serpula, Terebellum, Spirorbis, Autodetus, Conchiolites, and Cornulites.