A genus of macroscopic green algae in which the thallus consists of elongated, hollow, tubular fronds with walls only one cell thick. The fronds may be simple or branched. The species are often difficult to distinguish from one another. E. intestinalis is a common species in Britain, occurring in rock pools on the upper shore and in estuaries; the thallus is typically irregularly inflated, giving the resemblance to an intestine, and may reach up to 1.5 m in length and 1.5–2.0 cm in diameter.
Subjects: Plant Sciences and Forestry.