1907] Collins,— Nomenclature for Algae 79 
effect, the first proposition of the kind as far as known to the writer, 
has been made by Prof. O. Nordstedt.! As Nordstedt is the highest 
authority on the desmids, was a member of the Congress of Vienna, 
and was appointed on the committee to take charge of the preliminary 
work on non-vascular plants for the Congress of 1910, his opinions 
should carry much weight. He considers in detail all the genera 
and many of the species of desmids, proposed in the first half of the 
last century, a chaotic assemblage. While some authors made con- 
tributions of merit, there is no one work that can be considered as 
at all complete to its time until we come to Ralfs, who in 1848 pub- 
lished The British Desmidieae; this work gives detailed descriptions 
and excellent figures of all the British forms, and has as an “ Appen- 
dix;" a list of all other known species, a large part of them also with 
figures and descriptions. With few exceptions all the literature of the 
desmids up to 1848 was gone over by Ralfs, and references noted; 
the few papers to which Ralfs does not refer have been analyzed by 
Nordstedt, and while they add a few synonyms to Ralfs’s species 
very little other change would have been necessary had Ralfs used 
them. ‘There are a few genera in Ralfs's work which might have to 
give place to older names if we could be certain where we are now 
doubtful, but as after careful study of the older authors the uncer- 
tainty remains and is likely to continue, Nordstedt considers that the 
wisest plan will be to adopt for the desmids the rule “The nomencla- 
ture begins with the British Desmidieae by Ralfs in 1848.” Asa 
second rule he provides that all names used by Ralfs in Brit. Desm. 
as of earlier authors, should be so quoted, but only as so attributed by 
Ralfs; for instance Euastrum oblongum Grev. sec. Ralfs, Brit. Desm. 
That this plan will simplify the nomenclature of the desmids is 
unquestionable, and that it will cause any serious inconvenience is 
unlikely. That Ralfs's monograph contains a few genera no longer 
classed as desmids can occasion no trouble, nor the fact that some 
of his genera have since been divided; that is merely what has always 
happened with increasing knowledge and discoveries of new forms. 
While in some cases Ralfs may have been misled by a faulty or hazy 
description by some older author, the chance of our now correcting 
this error is too small to outweigh the real gain of accepting Ralfs's 
definite description and clear figure, and working from them. 
1 Algological Notes 1-4, 1. The starting point of the nomenclature of Desmids. 
Botaniska Notiser, 1906, p. 97. 
