|This section requires expansion. (September 2013)|
The thallophytes (Thallophyta or Thallobionta) are a polyphyletic group of non-mobile organisms traditionally described as "thalloid plants", "relatively simple plants" or "lower plants". Several different definitions of the group have been used. Most authors define the thallophytes as having undifferentiated bodies (thalli), as opposed to cormophytes (Cormophyta) with roots and stems. They were a defunct division of Kingdom Plantae that included fungus, lichens and algae and occasionally bryophytes, bacteria and the Myxomycota. They have a hidden reproductive system and hence they are also called Cryptogamae (together with ferns), as opposed to Phanerogamae.
Stephan Endlicher, a 19th-century Austrian botanist, separated the vegetable kingdom into the Thallophytes (algae, lichens, fungi) and the Cormophytes (including bryophytes and thus being equivalent to Embryophyta in this case) in 1836.
In the Lindley system (1830–1839), Endlicher's Cormophytes were divided into the Thallogens (including the bryophytes), and Cormogens ("non-flowering" plants with roots), as well as the six other classes. Cormogens were a much smaller group than Endlicher's Cormophytes, including just the ferns (and Equisetopsida) and the plants now known as lycopodiophytes.