Brighton, on a plank between high and low water mark, Mr. Borrer;
Bocks by the Sea, Penzance, Mr. Ralfs.
Geoeg. Dis tr . Coast of Prance.
Desok. Stratum of indefinite extent, firm, membranaceous or coriaceous, peeling
off in large flakes, without much lubricity, and without gloss when diy, of
a dark green when growing above high-water mark, and a blueish green
when submerged. Mlaments slender, densely interwoven together, twisted
Uke the letter S, or like a corkscrew, radiating in all directions.
The specimens from the South of England are of a much
brighter colour, and the stratum thinner than in the original
Scotch specimens, but the microscopic character is very similar.
Whether the 0. subsalsa of Agardh be different, 1 am unable to say.
B. Pig. 1. Oscillatoria spiralis ; part of a stratum :—o f the
2. Pilaments :—highly
P l a t e CV. C.
SPIRULINA TENUISSIMA, Kütz.
G e n . C h a r . Mlaments lying in a mucous layer, rigid, simple, spirally
twisted, vividly oscillating. Tube continuous; endochrome green,
more or less distinctly annulated.— S p ir u l in a {Turp.). a diminutive
fa , a twist or curl.
S p ir u l in a tenuissima; “ stratum very lubricous, æruginous, subradiant;
filaments densely spiral, very slender, parallel, flexuous” .
Spirulina tenuissima, Kiitz. Bhyc. Gen. p. 183. Balfs, in Ann. Nat. Hist
vol. xvi. p. 309. PI. 10.
H a b . On decaying Alga in a brackish pool near the Menai Bridge, and on
sticks in brackish pools at Penman Pool near DolgeUy, Mr. Ralfs.
Aberdeen, B r. Bickie.
Geogr. Distr. Em-ope,
Desok, “ I t forms at first a thin pellicle of a rich green colour, but in an advanced
state becomes somewhat skin-like and tinged with brown; the filaments
are extremely slender, of a pale blueish green colour, elongated, straight
when free, equal, not attenuated at the extremities, vividly oscillating.
Spires very close, Uke the volutions of some shells, broader than long.
There is no appearance of granular matter, and the filaments are so fine
that I cannot ascertain whether they are Jointed ” . Balfs. I. c.
Having never seen this plant in a living state, I prefer giving
Mr. Ralfs’ excellent description in his own words. I am indebted
to Dr. Dickie for beautiful dried specimens, from one of which
my figure has been taken.
C. Pig. 1. SpiEULiNA TENUISSIMA, part of the stratum ;—o f the natural size.
2. Pilaments, ;—highly magnijitd.