8 
HISTORY OF CLASSIFICATION 
mosses, ferns and conifers and definitely determined two critical points 
as represented by a single cell in the life cycle of each, namely the spore 
and the fertilized egg-cell and showed the essential homology of the 
sporophytic stages and the sexual stages in all these groups. His results 
were truly of vast and far-reaching importance in systematic botany, 
because no one could doubt thereafter that there is a genetic affinity run¬ 
ning through these great divisions of plants. The main outline of the 
theory has since been successfully extended to the flowering plants. I 
should like to stress the point, however, that Hofmeister himself does not 
propose any such genetic theory but is content to state his results clearly, 
concisely and convincingly. He has been called the master genius of 
descriptive botany and there is no difference of opinion amongst any 
class of botanists as to the place accorded him in botanical history. S. 
L. Endlicher was the author of a Genera Plantarum in which the groups 
were described with great ability and clearness and fullness, the char¬ 
acters which bring families, genera and species into connection were set 
forth in such a way that this work was for reference of the greatest use 
to all subsequent investigators. For us in California the name of End¬ 
licher h&s an especial interest since it was he who first recognized the 
Redwood as a distinct generic type and erected for it the genus Sequoia. 
The middle years of the Nineteenth Centurv witnessed the high tide of 
development of the science of plant morphology and has been called the 
Heroic Age of Plant Morphology. The brilliant work in systematic 
botany and the fragments of the natural system as worked out came into 
the hands of and was used in important arguments by Charles Darwin, 
author of the “Origin of Species,” and produced that tremendous fer¬ 
ment in the biological sciences which is evidently destined to continue 
for so long a period. Morphology henceforth became the servant of 
phylogeny. 
The only general work which presents one entire view of the plant 
kingdom was projected by Adolf Engier and Karl Prantl under the title 
Die Naturlichen Pflanzenfamilien, the Natural Families of Plants. Begun 
in 1880 and finished in 1908 it is in every way colored by the doctrine of 
evolution. While arranged after a theory of phylogenetic sequence it 
has also the great merit of presenting not only the systematic char¬ 
acters of the families but their special physiology, histology, biology, 
embryology, geographic distribution and similar matters as well. The 
linear sequence begins with the Gymnosperms which, it is agreed, both 
by the morphological and geological evidence, are the oldest seed plants. 
Most probably they are derived from Pteridophytes independently, and 
are in themselves polyphyletic and not monophyletic. Monoctyledons, 
occurring at the end of the Bentham and Hooker series, are placed next 
by Engier and Prantl. At the beginning of the Dicotyledenous series 
they place the catkin-bearing families, the oaks and their allies, followed 
by the nettles, buckwheats, chenopods and other apetalous families. The 
dicotyledenous series ends with Compositae where it undoubtedly should 
be placed. 
The sequence of families, as represented in this little text, is in a way, 
in part, a reversion to the system of Bentham and Hooker, but with an 
