1896.] Botany. 827 
simple to the more complex.” * * “Systematic arrangement should 
logically follow the natural order.” * * “ The sequence of families 
adopted fifty or seventy-live years ago has become incongruous with 
our present knowledge, and it has, fur some time past, been gradually ` 
superseded by truer scientific arrangements in the later works of Euro- 
pean authors.” “The more simple forms are, in general, distinguished 
from the more complex, (1) by fewer organs or parts; (2) by the less 
perfect adaptation of the organs to the purposes they subserve ; (3) by 
the relative degize of development of the more important organs; (4) 
by the lesser degree of differentiation of the plant body or of its organs; 
(5) by considerations of antiquity, as indicated by the geological record ; 
(6) by a consideration of the phenomena of embryogeny. Thus, the 
Pteridophyta, which do not produce seeds and which appeared on 
the earth in Silurian time, are simpler than the Spermatophyta; the 
Gymnospermae in which the ovules are borne on the face of a scale, 
and which are known from the Devonian period onward, are simpler 
than the Angiospermae, whose ovules are borne in a closed cavity, and 
which are unknown before the Jurassic.” 
“In the Angiospermae the simpler types are those whose floral 
structure is nearest the structure of the branch or stem from which the 
flower has been metamorphosed, that is to say, in which the parts of 
the flower (modified leaves) are more nearly separate or distinct from 
each other, the leaves of any stem or branch being normally separated, 
while those are the most complex whose floral parts are most united.” 
“ The sequence of families adopted by Engler and Prantl, in ‘ Natür- 
lische Pflanzenfamilien’ above referred to, has been closely followed in 
this book, in the belief that their system is the most complete and 
philosophical yet presented. The sequence of genera adopted by them 
has, for the most part, also been accepted, though this sequence within 
the family does not attempt to indicate greater or less complexity of 
organization.” 
he nomenclature is that of the well-known Rochester-Madison 
Rules of the Botanical Club of the American Association for the Ad- 
vancement of Science, and, in order that the student may fully under- 
stand the matter, the rules are printed in full, with explanatory notes. 
As this work will at once become the standard botanical manual every- 
where in this region for which it is designed, the revised nomenclature 
will soon be more familiar than the old which it is rapidly superseding. 
The work proper opens with the family Ophioglossaceae, the lowest 
of the Pteridophyta, in which one species of Ophioglossum, and six of 
Botrychium are described and figured. Then follow Osmundaceae (3 
