194 Rhodora [OCTOBER 
make clear verbally. They seem carefully done and will undoubtedly 
prove very useful. A third innovation lies in the adoption of the Vienna 
code of nomenclature throughout the work. This has necessitated a 
change in many familiar names, but in fewer than would have been the 
case had a more radical system been adopted. We also find evidence 
throughout the work of painstaking investigation into the types of the 
older authors, resulting frequently in the discovery of long-followed 
error in interpretation. Rectification of such error has also resulted 
necessarily in some change of names. 
The older botanist will also find much evidence of the great activity 
in taxonomic botany of recent years. Many species are added; 
others are broken up; while some are united, in accord with recent 
revision of the various groups. In this however the authors have 
maintained a conservative attitude, critically reviewing all new pro- 
positions, omitting species of doubtful status, and treating as varieties 
all those forms that freely intergrade. ‘The policy has also been,— 
when in doubt, leave it as it was. 
We note also the introduction of many specific keys under difficult 
genera. To the reviewer this seems a very commendable feature, 
but one that might well have been introduced much more freely. 
The genus Aster and the genus Solidago show very strikingly this 
contrast in treatment. Another new feature, also a good one, is the 
addition of synonymy under each species. This will be especially 
appreciated by the amateur botanist who has not time to follow all 
the changes in nomenclature. 
The liverworts have been omitted from this edition, but the ferns 
and their allies are still retained. ‘The plates that were found at the 
back of the book are also omitted, most of their figures having been 
redrawn and more conveniently distributed in the text. At the 
beginning of the book the synopsis of families has been much reduced, 
and the analytical key has been made to occupy a more prominent 
place. 
Notwithstanding these many innovations the book is still recogniz- 
able as а Gray's Manual. Throughout the work the well known 
"manual" practice of italicising the distinguishing characters has 
been followed in family, generic, and specific descriptions. Following 
the family characterization of the larger families we also find the fa- 
miliar synopsis divided into tribes with the subdivisions marked with 
the asterisk and the dagger, and we also find the interpolation in the 
