278 Kansas Academy of Science. 



ther to the child. We have yet to learn of a man being father to a man 

 like himself without the young man's first passing through the formative 

 period of childhood. The passing of a youthful sporophyte into a numer- 

 ously represented adult gametophyte through the intervention of a multi- 

 tude of spores is one of the important differences between plant life and 

 animal life. The feature belongs distinctively to plant life and is not to be 

 explained by anything in animal life, which is an entirely different king- 

 dom. 



In all archegoniates creation is indeterminate. Only enough of the 

 plant is organized in the oospore to start the sporeling on a good, healthy 

 growth. Creation, though it necessarily precedes, is continuous with de- 

 velopment, as distinctly seen in the coil of the fern frond. Yet there is a 

 limit to creation and development. Food supply, gravity and strength of 

 materials, season, temperature, etc., are all barriers that Hmit growth. 



Thera are two main phyla of this subkingdom, namely: (i) Bryophyta, 

 or mosses and liverworts, and (ii) Pteridophyta, or ferns, horsetails and 

 club mosses. 



Phylum I. BRYOPHYTA (Muscineae). 



Mosses and Liverivoris. 



Chlorophyl-developing, nonsaprophytic, nonparasitic, cellular plants, usu- 

 ally small, rarely exceeding 10 cm. in height, often no more than one milli- 

 meter, germinating in moist, damp or wet places, and consisting of green, 

 prostrate or erect stems and branches of various forms, with or without 

 rudimentary leaves. 



Gametophytes, which are conspicuous and comparatively long-lived, de- 

 velop from a spore, and may multiply vegetatively by minute budlets 

 (gemmae), by offshoots (innovations), or by runners. Antheridial or arche- 

 gonial bodies, or both, are later formed on the main stem or branches. 

 These give rise to new forms (sporophores) situated upon them, that finally 

 bear asexual spores as in the beginning. All phases of life are cellular; the 

 sporophores, which are only parts of plants after all, like the stalked cap- 

 sule of a carpellate plant, are never a separate generation, but are stationed 

 on top of the oophoral or gametophytic plants and depend upon them for 

 existence. 



The fruit-bearing bodies are (a) antheridia, which are simple, club- 

 shaped, sperm-bearing organs, in which each antheridium bears numerous 

 cells, each of which contains a single spirally-curved biciliated sperm or 

 antherozoid; and (6) archegonia, flask-shaped bodies, each of which contains 

 a single ovum or ooid cell at the bottom. Fecundation takes place under 

 water by the antherozoids swimming to the summit of the archegonium and 

 working their way down the narrow channel in its neck to the ovum at the 

 bottom, with which one of the antherozoids, and one only, fuses. Rain, 

 heavy dew or melting snow provides sufficient water for this purpose. 



After impregnation the ovum germinates immediately and gives rise to 

 a stalked spore-case (the sporophore) which contains very many nonsexual 

 sp )res, any of which on escaping may develop into a nonchlorophyl-bearing 

 thillus or protonema, from which the oophoral liverworts or mosses later 

 arise by budding. 



There are two classes in this phylum, namely: (i) Marchantineae, or 

 liverworts, and (ii) Bryinese, or mosses in general. 



