828 The American Naturalist. [October, 
species), Hymenophyllaceae (1 sp.), Schizaeaceae (2 sp.), Polypodiaceae 
(59 sp.), Marsileaceae (2 sp.), Salviniaceae (2 sp.), Equisetaceae (11 sp.), 
Lycopodiaceae (11 sp.), Selaginellaceae (3 sp.), and Isoetaceae (8 sp.). 
The flowering plants, as we have been calling them, are here more 
correctly called seed-bearing plants (Spermatophyta), and are properly 
divided into two classes—Gymnospermae and Angiospermae, and the 
latter into the sub-classes Monocotyledones and Dicotyledones. As one 
turns over the pages, reading the full descriptions and comparing them 
with the excellent illustrations (which are always by the side of the 
descriptions) the conviction deepens that this book is one of the most 
important systematic works yet produced in this country. This is well 
illustrated in the treatment of the sedge and grass families which fill 
two hundred and sixty-six pages. Any one who has tried to puzzle out 
the genera and species of grasses and sedges will not have to be told of 
the great advantage which good figures will give to the student of these 
difficult families. It is not too much to say that no publication 
hitherto made has done so much to popularize the study of these plants 
as the one now before us. Of Carex alone two hundred and five spe- 
cies are figured ! 
We have not the space at our command to speak of the many 
changes in generic and specific limits with which this work will famili- 
arize us. Nearly all of these have been known to specialists and those 
who have kept their eyes on the work of the German systematists, but 
to many the changes will come as novelties. 
Among the minor matters may be mentioned the abandonment of 
the absurdity of calling families “ orders,” thus conforming to the usage 
in other departments of biological science. All family names (with a 
very few exceptions) are now made to end in aceae, a commendable 
practice which Dr. Gray used to insist upon. Throughout the work 
all diphthongs are printed in separate letters (ae, oe), and not in single 
characters (œ, œ), thus again conforming to the German usage. In the 
rules for pronunciation, a little easement is made for the use of the 
Roman pronunciation of botanical names, which we wish had been 
made a little more evident. We regret to see the use of feet, inches 
and lines still adhered to in this otherwise modern work. The metric 
units are so generally used in scientific books everywhere that we are 
surprised at this unexpected anachronism. 
As we carefully study the beautifully-printed pages of this work, we 
are more and more impressed with its magnitude and importance. It 
will give renewed life and vigor to systematic botany, and doubtless 
- will be the means by which many a student will be led to the study of 
