142 AMERICAN MIDLAND NATURALIST. 
used in monographs and important floristic works up to 1890. 
The list of these names forms an appendix to the rules of Nomencla- 
a 
The obvious reason for this arbitrary and sweeping exception to 
the law of priority since 1753 ‘‘zs to avoid changes in nomenclature.’ 
Has this been affected? As the rule may be and actually has been 
interpreted any change may still be made of a plant name which ac- 
cording to the rule is not in the list though it may have been in 
use up to 1890 for fifty years. In Gray's Manual, seventh edition, 
we find several such changes, and changes of names that had been 
up to the present time in use, for not only fifty years but actually, in 
one case, for one hundred and fifty years! Such changes are more- 
over, made by those who claim that they have ''scrupulously endeav- 
ored to bring the nomenclature of the manual in accord with th 
Vienna agreement in order that American nomenclature may be 
freed as speedily as possible from peculiarity or provincialism, and 
assume the form which has received international sanction.”” 
Limnanthemum was applied as a name of a segregate genus 
from the Linnaean Menyanthes by Gmelin in 1769, and there has 
been no other name used for it as a separate genus, up to 1908, the 
year of the seventh edition of Gray’s Manual. It was found, how- 
ever, the Limnanthemum had not priority and a name completely 
forgotten, Nymphoides, Hill 1756 substituted. As the name has 
priority no one could object to it except for etymological reasons 
which Linnaeus y gave more than a century and a half ago. 
Whatever the reason there be for changing U/maria to 
Filipendula, the latter is new and the former has been used for 
more than a hundred years. Added to this U/maria is as a matter 
of fact as old as Filipendula even since 1753, both having been 
published by Hill; in 1756.1 
The best reason why Nymphoides” can be used for Limnanthe- 
mum according to the rules is that it is not on the list of condemned 
names, though we feel sure that had that eminent assembly thought 
of the name it would certainly have been put on the list. The only 
way to do away with it according to international rules is for 
botanists to assemble again and condemn it. 
I do not wish to cast a slur either on congresses which are not 
* Gray's Manual, 7th phus 1908, Preface, p. 7. 
t Hill, J. British Herbal. 1 
- Í Linnaeus, C. Historia Nds 1751-1754. 
