BOTANY: E. W. BERRY 
331 
Furthermore can any characters be mentioned which in the light of 
paleobotanical knowledge and evolutionary theory are more illogical as 
the basis for the characterization of great groups than siphonogamy, 
or the number of cotyledons, or the great stress that is laid upon the 
morphology of flower parts in the classification of the socalled flowering 
plants. 
The attempt to force the vegetation that clothed the earth five or 
ten, or fifteen miUions of years ago into the taxonomic bounds formu- 
lated for the flora of a single geological period, namely — the Present, sug- 
gests the petrified asters (Sphenophyllum) which Lehmann described 
from the Carboniferous, or the cacti, galiums and euphorbias which 
Lindley once described from the English Coal Measures. 
During the long ages of the Paleozoic there were at least four dom- 
inant major groups of land plants and a fifth should probably be added, 
since while the true ferns were not as numerous as was once supposed, 
the other groups show more or less evidence of having had ferns for 
ancestors. These other groups that were dominant in the Paleozoic 
are those of the seed ferns, the Lepidodendrons (and their allies), the 
Calami tes (and their allies) and the Cordaites (and their allies). What 
can be said of a practice which unites in a single order such complex 
arborescent quasi seed plants as some of the lepidodendrons and exist- 
ing club mosses separated by a time interval of many millions of years 
and by an almost equally great structural gap? 
During the Mesozoic the dominant plants were the ferns, cycad-like 
plants, conifers and ginkgoes, all of which underwent adaptive radia- * 
tions on all of the continents and which should form the basis for a 
dozen natural orders instead of but four, in fact Nathorst has already 
proposed that the cycad-like plants shall constitute a separate phylum — 
the Cycadophyta. 
The proposals that follow were formulated in 1910 and have been 
tested in university and research work during the interval that has 
elapsed. They were used in an article on Paleobotany for the new 
International Encyclopedia (1915) and are put forward in a somewhat 
categorical manner at the present time as a summary of the present 
status of paleobotanical knowledge and as an invitation for comments 
from competent critics. 
