[Vol. 2 



112 ANNALS OF THE MISSOURI BOTANICAL GARDEN 



(b) Gametophytes hysteropliytic, dependent upon, and nourished by, the 

 sporophytes, the megagametophyte not containing chlorophyll. 



(1) Megagametophyte a fully developed cellular mass before the forma- 

 tion of the eggs; microgametophytes few-celled; antherids basieidal; 



sperms ciliated and motile; megasporophylls open, in simple spirals to 

 simple strobili; seeds fleshy; microsporophylls mostly multisporangiate ; 

 bundles tracheidal, in a small, little-enlarging cylinder; pith and cortex 

 large; steins simple; leaves ample, mostly pinnate, persistent, veins 



parallel cycad phylum 



(2) Megagametophyte a fully developed cellular mass before the forma- 

 tion of the egg*; microgametophytes few (to one) -celled; antherid apicidal; 

 sperms non-ciliated and not visibly motile; megasporophylls open, in well- 

 developed strobili; seeds not fleshy; microsporophylls with few (2-8) 

 sporangia; bundles tracheidal, in an enlarging cylinder; pith and cortex 

 small; stems branched; leaves small, simple, persistent, veins parallel 



C0N1I-KJR PHYLUM 



(3) Megagametophyte fully developed as a cellular mass (endosperm) 

 only after the fertilization of the egg; microgametophytes one-celled; 

 antherids apicidal; sperms non-ciliated and not visibly motile; mega- 

 sporophylls closed (carpels), in floral strobili (flowers), often much 

 reduced; seeds not fleshy; microsporophylls (stamens) with four sporangia; 

 bundles fibrovascular, in an enlarging cylinder; pith and cortex small (or 

 bundles scattered and stem non-enlarging) ; stems branched; leaves mostly 

 large, simple to compound, persistent to deciduous, veins netted to parallel 



FLOWER] NG PLANT P IIYLUM 



In the foregoing analysis, I have emphasized the similarities 

 rather than the dissimilarities between the plants of these 

 phyla, and such a statement will serve to show thai they are 

 related, and yet no one can compare them and not be forced 

 to the conclusion that they must have diverged from one an- 

 other at an early period in their evolution. And this diver- 

 gence is to be interpreted as involving the cycad phylum as the 

 primitive group from which have sprung the conifers on the 

 one hand and the flowering plants on the other. 



Following the plan which I adopted in my earlier paper, 1 I 

 may here designate a number of generally accepted principles 

 of classification as they apply to the flowering plants. AVhile 

 generally accepted, these principles have rarely if ever been 

 formulated by taxonomists or others, so that as here formu- 

 lated they may create some surprise and perhaps some oppo- 

 sition. 



For the sake of brevity I give them in the form of dicta, as 

 rollows: A general dicta 



1. Evolution is not always upward, but often it involves 



degradation and degeneration. 



1 Lor. cit. 



