U LV A umbilicalis.
P e lta te L ave r.
CRYPTOGAMIA Algae.
Gen. Char. F ro n d membranous or gelatinous. Seeds
solitary, scattered throughout its substance, under
the cuticle.
Spec. Char. Somewhat coriaceous, orbicular, sessile,
peltate, spreading nearly flat, variously lobed.
Syn. Ulva umbilicalis. Linn. Sp. P I. 1633. Huds.
567. With. v. 4. 121. H u ll. 311. L ig h tf. 967.
U . marina umbilicata. Dill, in R aii Syn. 62.
Tremella marina umbilicata. D ill. Muse. 45. t. 8.
/ • 3.
]STo t rare on the sea coast, where it grows solitary and dispersed,
adhering to stones and rocks by its central root, and
is often thrown up on the more sandy shores.
Its substance, membranous when young, becomes considerably
thickened, and almost coriaceous, not adhering to the
papers in which it is dried. The colour is purplish with a
tinge of brown and green; sometimes altogether a dull purple
; but the surface is shining and very smooth. Each plant
is about a span wide, often much more, somewhat orbicular,
variously cut or lobed even to the centre, the edges crisped
and wavy, the substance frequently torn by the wind or
waves. The whole, under a magnifier, being finely and regularly
cellular within, looks dotted. Here and there are seen
a few seeds, dispersed in small clusters, darker than the frond.
These Mr. Turner has sent us. Mr. W . Borrer, to whom we
are obliged for the larger specimen, observes that Roth’s
U. purpurea, Catalect, v. 1 . 209. t. 6 . ƒ . 1 , is merely an oblong
variety of this.