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APPENDIX
TO CHLOROPHYLLOPHYOBÆ.
In the form of an Appendix we shall here enumerate a few
speoies, of doubtful position, which are not known with sufficient
exactitude to be recorded in systematic order, although their
affinities appear to be with the Alga;. The Saprolegniece are
not included, because they are now generally acknowledged as
Fungi. The genns Synchitrhim also appears to he more nearly
related to Protomyces, amongst Fungi, th an to Algte.
F a m i ly . CHYTRIDIBH].
Plants for the most part aquatic, parasitic, epiphytal or endo-
phytal, oooasionally epizoic, very rarely terrestrial, one or two-
celled. Cells vesiculose, single or gregarious, either innate in
the fostering plant, or penetrating its membrane ; furnished
with radicles at the base, or destitute of them ; now and then
numerous and densely aggregated, involved in a common membrane,
nestling in the parenoliyma of terrestrial plants, and forming
pustules. Protoplasm mucilaginous, usually colourless,
sometimes coloured. Antheridia not yet observed. Propagation
by oospores or zoogonidia.
Some authors have united the majority of the speoies under the one
genns Ohytridium, whilst others have distributed them over several
genera, aa Chytridium, Phlyetidmm, Bhyzopliidiwm, Olpidnm, and
Rhizidium, but apparently without good reason.
Genus 76. CHYTRIDIUM. Braun. (1851).
Cells globose or somewhat pear-shaped, operoulate above, the
root-like base usually innate in various alg», penetrating the
membrane of their cells.
Zoogonidia very numerous, globose, with a nucleus, bearing a
single very long cilium, escaping through the orifice of the cell
caused by the falling away of the operculum.
“ The Chytridia, form a genus of unioellular, parasitical Algæ, or, if it
be preferred, of aquatic Fungi, related to Saprolegnia about as much as
Asoidium is to Bryogjsis. The entire plant is composed of a single balloonshaped
cell, which penetrates into the Algæ upon which it grows, by a
more or less developed root-like base. The inflated portion of the cell is
filled with colourless mucilage, from which are formed, not through successive
division, but by a simultaneous process, very numerous small
globular germ-cells, which exhibit a sharply-defined darker nucleus m the
interior, and possess a single very long cilium. From their want of
colour and the activity of their motion these gomdia resemble the rnost
minute monads. Their extrusion occurs either through the casting ott ot
a lid or through mere tearing of a nijiple-Yaped point. Of fifteen different
speoies which I have observed in the vicinity of Freiburg, Ghytndmm
olio, is the largest, and at the same time exhibits the lid-like dehiscence
most beautifully. It grows on the anterior wrinkled end of the bulging
parent-oells of the spores of OEdogouium LaiidsborougUi, the root penetrating
into the folds and attaching itself to the spore. The free inflated
portion of the cell is ovate, with the lid somewhat thrown up at the
edges, and apiculated like a short nipple in the middle. The germ-cells
are about 003 mm. diam.”—BraM», Bejuvenescence, pp. 186 note.
See also Braun, “ üeber Chytridium ” (Berlin, 1856) ; Cohn in Htó-
wigia,” 1865, p. 170 ; Nowakowski “ Beitrag zur Kenntmss der Ghytri-
diaoeen’ (Breslau, 1876).
C h y tiid ium a cum ina tum . Braun Chytr. p. 28, t. 1, / . 11.
Cells much smaller than in Chytridium olla, ovate-pyriform ;
operculum acuminate.
S iz e . Cells -016 mm. long.
Kabh. Alg. E u r. iii., p. 277.
Parasitic on speoies of OEdogonium.
Plate L X X X I . fig. 1. Chytridium acuminatum parasitic upon (Edo-
gonium Bothii X 400 diam.
Genus 77. RHIZOPHYDIUM. Scherik. (1858.)
Cells globose, ovate, or broadly clavate, with 2, 3, or more
scattered orifices, more or less elongated into a neck, furnished
with, or destitute of, distinct radicles at the base.
Rhizop h yd ium B a zk e iian um . {Archer) Babh. Alg. Pur. in . 281.
Cells much depressed, 3 or 4 lobed, the lobes broadly rounded ;
upper surface of the cell concave, bearing at the centre a vertical
hyaline, very slender, terete, minutely capitate process ;
cell contents mainly confined to the centre, leaving the ends of
the lobes empty; zoospores making their exit through the
opened apices of the lobes.
Chytridium Barkerianum, Archer in Quart. Journ. Micr. Sci.
1867, p. 89.
Parasitic on Zygnema. Callery Bog (Ireland).
We have seen no specimens, and are not aware of any figure extant, or
of any dimensions having been recorded.
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