CORMOPHYTASTER AND XENIOPHYTE. 239 



in the mossworts that possesses stem and leaf, the non-sexual or 

 sporophytic generation being undifferentiated, so that no real homol- 

 ogies are to be traced between the shoot of a mosswort and the 

 shoot of a fern wort or seed plant. Hence it comes that careful 

 botanists do not fall into the popular error of treating the moss- 

 worts as cormophytes because mosses and liverworts have what we 

 usually speak of as stem and leaf, though the fact may be obscured, 

 perhaps even when stated, that greater morphological reasons dictate 

 the entire abandonment of the old and in a way convenient but now 

 meaningless division of the Vegetable Kingdom into flowerless and 

 flowering plants, in the former of which the heterogeneous as- 

 semblage called thallophytes and the well-defined taxonomic groups 

 bryophytes and pteridophytes stand as coordinated. Even though 

 we abandon thallophyte and cormophyte as of serious taxonomic 

 use just as the subdivision of the former into fungi, algse, and lichens 

 is recognized as more suited to popular than to scientific diction, the 

 essential fact remains that these two words, properly defined, stand 

 for realities in morphology, which, supplemented by a comparable 

 designation for the mossworts (which now bear only the group 

 name bryophytes, comparable with pteridophytes and anthophytes or 

 spermatophytes), divide the Vegetable Kingdom into three main 

 divisions : Thallophytes, with the body undifferentiated into 

 morphological root, stem, and leaf ; Cormophytasters or pseudo- 

 cormophytes, with differentiation of the sexual generation into 

 cormoid and phylloid. — the so-called stem and leaf ; and Cor- 

 mophytes, with differentiation of the non-sexual generation into 

 root and shoot, and of the latter, usually, into true stem and leaf. 



Recognition that with these gross characters are associated 

 numerous structural details (e. g., the absence of a specialized dif- 

 ferentiation between sexual and non-sexual generation even in 

 those thallophytes which by their nuclear behavior show an alterna- 

 tion of generations ; the presence — as in many algas — of pyrenoids 

 and of large chromoplasts in the sexual generation of the liver- 

 wort Anthoceros, and of stomata — as in mosses and cormophytes — 

 on its unusually evolved non-sexual generation ; the appearance of a 

 rudimentary conducting strand in the non-sexual generation of this 

 liverwort and of mosses ; the universal development of stomata and 



