PROCEEDINGS OF SOCIETIES. 69 
In Mr. Archer’s plant instances of such series of quadrate cells 
were frequent, but in no instance were they found empty, nor 
could he see any indication as to which he would feel at all satis- 
fied that in his plant these peculiar cells were the mother-cells of 
androspores. Yet it is probable they may have been, for, although 
he had not been able to perceive the origin of the androspores, the 
dwarf male plants were present in abundance, and the andro- 
spores from which they were produced must have originated 
somewhere, although this was, unfortunately, failed to be made 
out. 
Again, Vaupell lays great importance on the terminal hair-like 
prolongation to the filaments, and he names his plant setigerwm 
accordingly. Now, this character is one met with in other forms, 
and Pringsheim attaches little weight to it, and Vaupell himself 
mentions (loc. cit., p.20) that even in his plant they were not always, 
but only mostly, found. Perhaps, however, like thé terminal mucro, 
which in Gidogonium Itzigsohni (de Bary) is certainly a special 
character, and seemingly always present in young plants (as 
pointed out by Mr. Archer at last meeting of the club), it may 
often become detached, and thus many of the filaments seem as if 
destitute of this prolongation. But be this as it may, and its pre- 
sence or absence worth what it may, in the plant now exhibited 
it may be most safely said that it does not exist at any time, which 
circumstance, so far as it goes, serves to remove it from Vaupell’s. 
And the presence or absence of these hair-like attenuated pro- 
longations may, perhaps, be of more value than Pringsheim sup- 
poses, inasmuch as Vaupell believes that the vegetative growth ot 
this part of the filament follows another plan from that of the 
ordinary Cdogonium-plant, m that here, he says, the growth is 
like that of ordinary Conferve, and that no “ cap-cells’” exist. If 
this be true, these hair-like prolongations exhibit a perhaps note- 
worthy differentiation of structure from the rest of the plant. 
With the foregoing exceptions, the present plant seemed quite 
to agree with Vaupell’s plant, the form, structure, and position of 
the dwarf male plants being alike, as well as that of the antheridia, 
spermatozoids, and oogonia. ‘Two oogonia sometimes occurred, 
indeed, in direct succession. 
By a fortunate coincidence, Mr. Archer was able to place on the 
able living fruited examples of some other_species of G@idogonium, 
as to which he thought no doubt could exist as to their identity 
with certain of Pringsheim’s species, though he had unfortunately 
been unable to preserve any specimens. These were Gidogoniwm 
tumidulum, Cegemelliparum (?), and Gi. Braunit. He was unable to 
lay hands on @. echinospermum, though he had met with it lately. 
He took the opportunity to mention that he had lately taken an 
(Edogonium which he could not but refer to @. Rothii, which 
presented the peculiarity of the oogonia being developed in direct 
succession to the number of eleven and lesser numbers. Although 
the number of eleven was not infrequent, it was perhaps singular 
that he had never once seen a greater. This peculiarity gave the 
