Size. Cells -OOD-OO? mm.; fam. -018 mm. fiiaJA.), cells
•004--006 mm. (C).
Rabh. Alg. iii. 24 ; Kircb. Alg. Schl. p. 115.
Protococcus valgaris, Kutz. Spec. p. 199.
Protococcus communis, Kutz. Tab. i., f. 8.
Pleurococcus communis, Desm. Exs. 1, 1203 ; ii. 603.
Hmmatococcus vulgaris, Hass. Alg, p. 383, t. 71, f. 5.
Ghlorococcum vulgare, Grev. So. Or., FI. No. 262.
On the trunks of trees, moist walls, &c. Common everywhere
throughout the year.
“ Plant of a lively full green colour, epreading very extensively over
the trunks of trees, and staining the fingers on the slightest touch. Granules
very minute, exceedingly numerous, densely aggregated, and form,
ing an uneven surface. They are perfectly free, semi-transparent, and
adhere together in an opposite manner by fours.”—Greville.
Plate II. fig. 1. a, natural size; b, cells X 400 diam.
P leurococcus an gu lo su s. (Corda) Meneg. Nost. f.4, f. 5.
Cells single, or 2-4, associated (64) in families, deep green,
nestling in greenish, rather gelatinous stratum, cell-membrane
thick, diaphanous.
S i z e . Cells -007-'013 mm. (Rabh.).
Rabh. Alg. iii. 25. Kirch. Alg. Schl. p. 115.
Protococcus angulosus, Corda in Sturm PI. ii. 18.
Microcystis angulosa, Kutz. Linnaja, viii. 374.
Protococaus palustris, Kutz. Tab. i., t. 4.
On the stems and leaves of aquatic plants.
In the^ Kew Herbarium copy of Rabenhorst’s Algas Exsioc, No. 327,
under this name, only Ghroococcus turgidus can be found, so that it is'
not quoted above.
Plate I I . f. 2. Cells magnified 400 diam.
P leurococcus (?) m uc o su s, Babh. Alg. iii. p . 26.
Cells very small, of variable size, single and 4-16, associated
in globose families, scattered, or aggregated in a gelatinous
green stratum. Cell-membrane very thin, hyaline, contents
homogenous, decussately divided; nucleus rounded.
S i z e . Cells -0023--0003 mm. (Rabh.).
Protococcus mucosus, Kutz. Tab. i., t. 4.
Hamatococcus theriacus, Hass. Alg. p. 333, t. 78, f. 9.
On the naked ground.
Dr. Allmann compares its appearance to inspissated syrup.
Plate I I . fig. 3. Cells magnified 400 diam.
P leuro co c cu s B e ig e lii. Kiich 8; Rahh.
Aerial, very small, very pale greenish, aggregated in numerous
globose families, encircling the hair. Cell-membrane rather
thick, colourless, contents very finely granular, sporangia containing
12-20 gonidia ; nucleus globose.
S i z e . Cells •006--0095 mm. (Rabh.).
Rab. Alg. iii. 27. .
“ The chignon fungus." Dr. Tilbury Fox, m “ Science
Gossip,” May 1, 1867.
On human hair used as “ chignons.”
This organism, which is included by Rabenhorst amongst Algae under
the above name, is rather a doubtful production, at least it seems to be
a doubtful alga. The late Dr. Tilbury Pox examined it carefully in
1867 with the following results
“ If you take a hair on which the parasite exists, and hold it between
yourself and the light, towards the outer half you will see one or more,
perhaps half-a-dozen, little dark knots, the size of pin points, surrounding
the shaft of the hair ; they are readily felt on drawing the hair
through the fingers ; they are somewhat difficult to detach. Under the
microscope, with a qnarter-inoh objective, the mass will be seen to be
made up of cellular bodies surrounding the hair. I t will be seen that
the mass has the appearance of a fungus growth, of which two distinct
forms are here present, viz., mycelial or filamentose, and sporular or
cellular. The hair is apparently healthy, and if the slide be pressed the
mass will break away from the hair on either side, bringing away with it
more or less of the cuticle, and leaving behind a healthy shaft. The
cells are seen to be of various shapes and sizes. They are from 1-4000
to 1-3000 of an inch, many are like the ‘ torula’ cells developed from
PeniciUum. Others are larger, undergoing division very actively. They
may be subdivided into two, three, or four parts, or much more freely.
This indicates the assumption by the parasite of an algal condition. ^ (It
is this form to which the name Pleurococcus Beigelii manifestly applies.)
“ In watching the mass on the hair carefully, it is evident that a
number of small cells become detached from the outer or sporular form,
and at once move actively about. These small cells indicate an active
growth by subdivision, and a fruitful source of propagation. Certainly
this variety of fungus, so far described, is the most active growth I have
come across in my researches, and I have been enabled to germinate it
most successfully, so as to set all questions as to its nature completely
at rest. Placed under favourable circumstances in water, the spores
enlarge considerably, and the mycelial filaments increase also, but there
is at this time to be observed a very remarkable occurrence, though not
in all cases. Some of the large cells have become filled with smaller
cells, and in others, in addition to these, processes have been put forth
from the circumference of the walls in a radiating manner; in other
cases the enlarged cells have two long cilia attached to them, by which
they move about rapidly, whilst a part of the hair previous to this free
from the fungus, has become dotted all over by minute cells similar to
those seen in the interior of the larger ones.
“ But more than this, I have observed most distinctly large cells filled
with smaller cells, furnished with exceedingly delicate radiating processes,
and putting forth pseudopodia. I t will here be seen to have
assumed the features of an amæboid body. Nothing could have been
more distinct to myself, and those who were observing with me, than
this peculiar form ; and it seems to me that we have here a pretty complete
history of the life of the fungus—namely, the sporular sub.
dividing and assuming an algal form, which in turn becomes amæbi-
form, and furnishes ciliated cells that supply the earliest condition of
the fungus, scattered over the hair.” Further details, with illustrations
are given in the memoir, of which the above is an abstract, to which the
student is referred.
Plate I I . f . 4. Cells magnified 400 diam.