iv PREFACE 
Another indication of the change that has taken place 
in the science is suggested by the fact that then the 
Plant Kingdom was divided into the ‘‘ Phaenogams”’ 
and ‘‘Cryptogams,” and that the usual sequence of the 
study was first proper “Botany” as a course in the 
structure, reproduction and classification of the “‘ Phaeno- 
gams,’’ with a possible Anhang of “‘Cryptogamic Botany”’ 
for such students as wished to invade this mysterious 
realm. How completely this has given way to a more 
scientific conception of the Plant Kingdom is shown by 
the practical disappearance of these terms from botanical 
literature and their relegation to more or less popular 
usage. 
Again, it was formerly the very general practice of 
teachers to present the subject of plant study beginning 
with the higher plants, and indeed devoting the far 
greater time to them, so that the sequence was from the 
higher to the lower forms. However, with the more 
complete acceptance of the doctrine of evolution the 
opposite sequence from the lower forms to the higher 
has become the general rule, since it permits greater 
emphasis to be placed upon the progressive structural 
changes by which higher organisms have been evolved 
from lower. 
In the earlier period there was not yet a general agree- 
ment as to the nature of the fungi,. and their relationship 
to the algae. They were treated for the most part as a 
group of quite isolated plants with only obscure if any 
relationship with other groups. They were contrasted 
with other groups, little attempt being made to empha- 
size similarities in structure, or to suggest possible genetic 
relationships. Today, on the contrary, we constantly — 
suggest to the students the probabilities as to the origin 
of each group of fungi. 
