Thallophyte

They form a division of kingdom Plantae that include lichens and algae and occasionally bryophytes, bacteria and slime moulds.

Thallophytes have a hidden reproductive system and hence they are also incorporated into the similar Cryptogamae category (together with ferns), as opposed to Phanerogamae.

Thallophytes are defined by having undifferentiated bodies (thalloid, pseudotissue), as opposed to cormophytes (Cormophyta) with roots and stems.

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.

[3] 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.