ORIGINAL COMMUNICATIONS. 
On the Proropuyta* of New Zeatanp. By W. Lauper 
Linpsay, M.D., F.R.S. Edin., F.LS., &c. 
CoMPARED with what has been already achieved, there 
remains, in certain departments of the Flora of New Zealand, 
much more yet to be accomplished—much that can probably 
only be properly executed by the resident or local botanist, 
who can leisurely study living forms on or near the locality of 
their growth. Of no groups of plants is this remark so true 
as of the Protophyta—the Desmidiacee, Diatomacee, and 
Palmellacee. The first and the last may be said to be almost 
or quite unknown; while our knowledge of the Diatomacee 
of the New Zealand islands is nearly altogether confined to 
my own local and limited collection from the neighbourhood 
* I quite concur with Prof. Smith and other systematists in separating 
the Dia/omacee aud Desmidiacee from the Alga, as a distinet order— 
Protophyla, which so far corresponds to the Pro/ozoa of the animal kingdom. 
There is quite as good ground for the separation iu the one case as in the 
other; the strongest argument, however, being, I believe, that derived from 
the convenience of the student and classificator rather than that any precise 
line of demarcation las been discovered by systematists. Such lines of 
demarcation, though plentiful in book classifications as “systems” so-called, 
are rarely, if ever, to be found in nature. For instance, as 1 have elsewhere 
shown (“On <Arthonice melaspermella,’ ‘Journal of Linnean Society,’ 
‘ Botany,’ vol. ix, p. 268; “Observations on Otago Lichens and Fungi,” 
‘Trans. Royal Society of Edinb.,’ vol. xxiv, p. 484), there is no real separa- 
tion between lichens and fungi, or between lichens and alga, though such a 
separation is assumed by all systematists. ‘ Natura non facit saltum:? her 
divisions are not definable by the “characters” of the systematist; she 
exhibits in both kingdoms a continuily of variation whereby variety passes 
into species, species into genus, and genus into order. The divisions of the 
systematist are artificial, arbitrary, provisional, and matters of convenience : 
the “species ” of one botanist is ot that of another, and what is a species 
to-day may become either a variety or perhaps even a genus to-morrow ; 
every addition to our catalogue of plants—every contribution from new 
countries or areas—leads to some modication of existing systems of arrange- 
ment and nomenclature. 
VOL. VII.—NEW SER. - 
