for in living nature there arc no abrupt unsightly chasms ;
all is uniformity, transition, design.
To the group Cystospermeoe are to be referred all the true
Confervoe; but before admitting any species as such, it is
necessary that it should undergo a rigorous examination ; for
wc find placed among the Confervoe proper many species having
no relation whatever with those near to which they are placed,
but are referrihle to some others of the genera belonging
to the other divisions of the Confervoe already established.
Thus C. alpina, C. purpurescens, C. zonata, C. punctata,
C. ericetorum, C. mucosa, are placed by Agardh the elder
and Harvey amongst the Confervoe properly so called. The
first two, nevertheless, are Conjugateoe, C. zonata and C. punctata
Sphoeropleoe, and C. mucosa a Desmidium.
It may he thought by some, that instead of instituting a
new generic name, it would have been better to have reserved
for the species included under it the old appellation of Conferva.
To the adoption of this course, two objections present
themselves ; the first is, that it appears unadvisable
that the term Conferva should ever be employed merely in a
generic sense—that a wider meaning ought to be extended
to the word— that It should be employed in the same manner
as the term Zoophyte, and made to embrace the filamentous
division of the Algæ; and the second is, that there is no
reason founded In right, why this term of Linnæus should
be perpetuated in any other way than that suggested, he,
and all Avho have hitherto employed it, having had no definite
ideas respecting the exact nature of the productions
Avhlch ought to be referred to it —Algæ widely difiering iu
essentials having constantly been placed under it.
Five of the six species of Proliféra described by Yaucher
are certainly to be referred to the genus Vesiculifera, the
sixth C. glomerata is of an entirely different nature. So imperfectly
and inaccurately, however, are those species described
and delineated, that it is impossible to identify them
with any degree of certainty. The following is Vaucher’s
account of the reproduction of the genus Proliféra, which, it
will be seen, is not In all respects inaccurate, though still,
for the most part, very erroneous : —
“ When the Proliferoe are ready to reproduce, cylindrical
enlargements are seen to arise in the length of the filaments,
which one would take for knots, if the plants were not articulated
or chambered. These bourrelets, at first but little
apparent, soon Increase in size, and finally become covered
with a pulverulent material, which is formed either by refuse
matter Avhlch fioats in the liquid, and Avhich has been retained
AvithIn the elevations, or of a material which Is secreted
by the Confervoe. When this poAvder has remained some
time upon the enlarged part of the stem, a number of filaments
are seen to Issue from it, which form at first little
rounded heads. Unfortunately this powder at the same
time that It seems to favour the Increase of the young Confervoe
baffles greatly the observer. He is able to see but
little of the first developement of the plant, and In consequence
is not able to judge, Avhether it issues from the surface
of the enlargement or from the centre : whichever it
may be, the young filaments extend themselves round all the
circumfei'ence, Avhere they form as it Avere a tu ft of hairs.
L ittle by little their cells begin to be marked out ; soon their
tubes resemble in miniature those of the great Prolferoe.
Lastly, they go and form elsewhere a new individual, like to
that from Avhlch they took their birth : but I acknowledge,”
says Vaucher, “ that I have not seen this separation, although
I have no doubt hut that it really takes place.”
What Vaucher regards as the young proliferous offspring,
are doubtless to be regarded as parasitic groAvths, to which the
Confervoe are peculiarly liable, more especially when they are
confined for a length of time in small vessels of Avater.
T avo other species of this group have been referred by
Meyen to a genus Hempelia, Avhich he Instituted for them, a
genus even more erroneously defined than that of Proliféra,
already noticed.
“ H empelia. — Thallus simplex, membranaceus, septatus,
æqualis vel inæqualls. Fructus terminalis est, capsula sub