thallus

thalloidThalloid of the liverwort Marchantia with gemma cups.

thallus, plant body of algae, fungi, and other lower organisms formerly assigned to the obsolete group Thallophyta. A thallus is composed of filaments or plates of cells and ranges in size from a unicellular structure to a complex treelike form. It has a simple structure that lacks specialized tissues typical of higher plants, such as a stem, leaves, and conducting tissue.

This article was most recently revised and updated by Amy Tikkanen.
Citation Information
Article Title: thallus
Website Name: Encyclopaedia Britannica
Publisher: Encyclopaedia Britannica, Inc.
Date Published: 24 February 2011
Access Date: February 22, 2025