in Hook. Brit. Flor. p. 389.; also in Manual, j). 122.
C. elegans Ag.
Ilab. On sticks, &c., in stagnant pools, common.
“ No sjiecics is more easy to recognise ; it is formed of
gelatinous protuberances of all sorts of figures, and of a
diameter Avhlch varies from a point to an inch.” — Vaucher.
5. ClIÆTOPIIORA PISIFORMIS Ay.
Plate IX . Figs. 5, 6.
Char. Frond subglobose, fleshy, green. Filaments sub-
dichotomous, obtuse. Sporidia globose, axillary. — Carm.
Harvey, in Hooker’s Brit. Flor. p. 389. ; Berk. Algæ, 1. 1.
fig. 1. ; Grev. Crypt, t. 150.
Ilab. In subalpine lakes.
Mr. Berkeley has discovered capsular fructification on this
species, and Kfitzing has figured similar capsules as belonglng
to C. tuberculosa. The occurrence of these capsules must be
regarded as excessively rare, and therefore commonly considered
as the only mode of reproduction possessed by species
Avhich are everywhere so abundant.
6. CHÆTOPHORA LONGÆVA Carm.
Char. “ Frond indefinitely effused, incrusling, gelatinous,
green. Filaments subdichotomous. Kamuli produced proliferous
towards the apex.” — Carm.
C. longoeva Harvey, in Hooker’s Brit. Flor. ; also in
Manual, p. 123.
Ilab. In a boggy stream at Appin : Captain Carmichael.
“ Fronds, continuous, or so closely set as to have th a t appearance,
of a delicate green colour, and more flaccid than
those of C. elegans, apparently from a deficiency of gelatine.
Filaments in all respects similar to those of other species,
excepting in being mostly proliferous.”
I cannot regard this as a distinct species, and Avould refer
to it C. endivioefolia or C. tuberculosa.
F am. VIII. CONJÜGATEÆ.
Char. Filaments simple, equal, often conjugating. E n dochrome
mostly figured. Sporangia yorwerf generally by
the union o fth e contents o f two cells, either in different or
in the same filaments.
The Confervoe, which we now propose to examine, are perhaps
the most curious of all their tribe. When viewed too
th e r , they form an exceedingly natural group, but one Avhich
Is defined rather by the enumeration of a number of characters
than by one in particular.
Their filaments when examined with the microscope are
seen to be simple and of uniform diameter; they are for the
most part unattached, and in their young condition are
smooth and unctuous to the touch, and of a deep green colour :
they are formed of an assemblage of elongated cells placed
end to end, and all of them enclosed and held in union by
an investing membrane, common to all, the interior of these
cells being occupied, chiefly with endochrome, which is
variously disposed, sometimes in the form of spires and stars,
a t others it completely fills their cavities : mixed up with this
endochrome, are observed numerous vesicles ; these being it is
presumed the unfertilized zoospores.
When the filaments have attained a certain age or period
of developement, most of the cells are seen to send forth a
little conical process, which unites with a similar protrusion
from a corresponding cell of a contiguous filament, an uninterrupted
passage of communication between the two cells
being thus established.
While this is occurring, the spiral tubes, if the species be
a Zygnema, become confused and coalesce in each cell, the con- ■
tents of one passing out through the passage of communication,
mingling with those of the other, and both uniting, are at
length moulded into a dark body of either an oval or circular
form, and enveloped in membranes ; and Avhich Vaucher,