PREFACE. 
In this work it has been the Author’s wish to adopt in all 
cases those names which have the claim of priority, unless 
good cause could be shown for a contrary proceeding, and 
with this object he has carefully examined nearly all the 
best European Floras, comparing our plants with the de- 
scriptions contained in them, and in very many cases with 
‘foreign specimens of undoubted authenticity. In the adop- 
tion of genera and species an endeavour has been made, by 
the examination of the plants themselves, to determine what 
are to be considered as truly distinct, thus, it is hoped, 
taking Nature as a guide, and not depending upon the au- 
thority of any name, however distinguished. Still let it not 
be supposed that any claim is made to peculiar accuracy, 
nor that the Author considers himself qualified to dictate 
‘to any student of botany, for he is well aware that there are 
many points upon which persons who have carefully studied 
