THE EVOLUTION OF PLANTS 
6lQ 
nothing but one particular stage in the evolution of the 
Vegetable Kingdom." 1 
TABLE VIII 
Ascendancy 
Periods 
Persistence and relationship of 
great groups 
VII. Reign of Angiosperms 
Tertiary 
Cretaceous 
Comanchian 
VI. Reign of Pro-angiosperms 
Jurassic 
Triassic 
Permian 
V. Reign of Acrogens (High- 
er Equisetes. Lycopods, 
etc.) 
Pennsylvanian 
Mississippian 
IV. Reign of Gymnospertns 
Devonian 
a a 
O.S. Q. 
O 
III. Reign of Early- 
Plants 
Land 
Silurian 
Ordovician 
5. Actual Fossil Land Plant rec- 
ord begins 
4. Primofilices Early Equisetes 
3. Basal Plant Complex with va- 
riety of species 
II. Reign of Algae 
Cambrian 
Precambrian 
(Proterozoic) 
2. Differentiation of Dry 
and Aquatic Plants 
(Fossil Algae abundant) 
Land 
I. Reign -of Primitive Life 
(Hypothetical) 
Old P re c a m- 
brian 
(Archeozoic) 
(Fossil Algse begin) 
i. Primitive Protoplasm and 
Unicellular Life 
In the above table (after Wieland), the groups are to be considered as 
arranged on an unrolled cylinder, projected from a hemisphere; thus the 
phyletic lines are to be pictured as converging above toward the pole, 
and the Cordaitales as coming between the Ginkgoales and Filicales, to 
both of which they are related. 
529. The Element of Geological Time. How many 
years has it taken for the evolution of the higher Angio- 
sperms that is, from the dawn of the fossil record in the 
1 Scott, D. H. "Studies in Fossil Botany," p. 3. 
