THE ZYGNEMACETE. 
82 8 
in all these cases the entire mass of protoplasm parts from 
the cell-walls and, in many cases, passes entirely out of the 
cell, leaving it to decay, which it speedily docs. Besides 
this the conception fails to account for the many curious facts 
in vegetable life already mentioned. The conclusions arrived 
at by all the mentioned observers are based upon investigations 
conducted by means of certain micro-chemical and staining 
reagents, and this brings me to the point of these remarks. 
Would it be possible to detect these delicate threads of 
protoplasm and to trace their connections without the use of 
reagents ? If this be possible, then we have in the Zygnenuicece 
the fittest material to work upon in the endeavour to elucidate 
these questions. For in the phenomenon of conjugation we 
have Nature herself acting as the plasmolysing agent, dissolving 
the bond of union between the cell-wall and the protoplasm. 
I have no practical or experimental knowledge to impart on 
these points ; but the attempt to solve them in the manner 
here indicated is well worth an effort ; and I here invite the 
younger and more vigorous of the botanical members of this 
section to devote a few all-night sittings to the observation of 
the phenomenon of conjugation with a view to contribute 
something towards a solution of these vexed questions. 
Rabenliorst, in his “Flora Europaea Algarum,” enumerates 
125 species of Zygnemacea ?, distributed in ten genera. Dr. 
Cooke, in his “ British Fresh-water Algae,” has subjected 
many of Rabenhorst’s species to a much needed revision, 
and has considerably reduced their number ; he describes 
thirty-seven species as occurring in Britain, distributed in 
eight genera. I myself have collected thirteen species 
determined—with two or three others not yet met with in 
fruit — in the immediate neighbourhood of Narborougli, 
including one that was new to the British list. 
In concluding I would strongly urge upon this Section 
how much it is to he desired that some of its botanical 
members forsake the more beaten paths of their pursuit, and 
seek “fresh fields and pastures new” in the study of the 
Fresh-water Algre. I can promise them a most exciting and 
interesting task. The field is large and there is room for 
many workers. Very much yet remains to be done : in fact, 
it might almost be said that the study of these plants has 
scarcely yet advanced beyond the incipient stage. Observa¬ 
tion and research are constantly proving that many so-called 
species, and even genera, are but stages in the life history of 
other species; and it is extremely probable that future 
research will place the bulk of the considered genera and 
species of the families PalmeUacea and Chroucoccacecc in the 
