One question, left unanswered by Hofmeister, was how the alternation of generations of the 'higher cryptogams' or archegoniates related to the life histories of 'lower cryptogams' or thallophytes.
the sporophyte) and is conventionally characterized as a conflict between theories of antithetic and homologous alternation of generations.
Celakovsky's (1874) purpose was to present an accurate classification of the alternation of generations (Generationswechsel).
Pringsheim (1876b) presented a contrary interpretation of the connection between alternation of generations in thallophytes and mosses.
Brown (1935: 657-658) clearly believed, however, that "it is doubtful if any alternation of generations .
An argument often put forward in favor of the homologous theory of alternation of generations (and sporophyte origin) is the alleged "evidence" of algae with isomorphic (morphologically identical or very similar) gametophytes and sporophytes, such as Ulva, Cladophora suhriana, Chaetomorpha (cf.
246) presented an easy-to-follow "flow diagram" of the evolution of meiosis, life cycles, alternation of generations, and so forth; their tracings led first to eukaryotes (after the development of mitosis and meiosis), and then to several major eukaryotic lineages and sublineages, including land plants based on the timing of meiosis in the life cycle and the supposed development of alternating generations.