7> ó [ 1554 ]
CRYPTOGAMIA Alga. *
Gen. Char. Seeds produced in round, solitary, closed
tubercles, projecting from the frond, but united
with it.
Spec. Char. Green. Filaments simple, very slender,
prostrate, closely entangled, somewhat rigid. Joints
very short, slightly swelled, with obsolete partitions.
Syn. Conferva muralis. Dillw. B rit. Conf. t. 6.
O f all vegetable productions this is perhaps one of the most
common upon damp walls, stones, and especially neglected
shady gravel walks. The dank areas in which the inhabitants
of crowded cities gasp for air, become verdant in the wet
months of winter with this Conferva, whose effects on the
atmosphere may perhaps be as beneficial as those observed by
Dr. Priestley in the species produced in corrupted water. Yet,
notwithstanding its frequency, this plant seems to have escaped
the mention of any writer before Mr. Dillwyn.
Its fibres are extremely slender, simple, twisted and entangled
together, pressed to the soil, which they cover with a
fine close green mat. Under a powerful magnifier they are
seen to consist of joints much shorter than they are broad,
either even or somewhat swelling, their partitions less conspicuous
than in most other kinds. Mr. Dillwyn has remarked
some of the joints to lose their green hue and become abruptly
colourless. No fructification is known.
Buddie’s observation, “ This I find like green satin lying on
gravel walks,” which Dillenius, in Rail Syn. 56. n. 1., applies
to Byssus velutina, (.our Conferva, t. 1556.) agrees exactly
with the plant aboye described.