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5. E uastrum a f f in e Balfs.
Plate XC. Fig. 9.
Char. Frond about three times as long as broad. Segments
pyramidal in front view, and thrice emarginate ; in lateral
view twice emarginate.
fl Frond about once and a h a lf as long as broad, twice
emarginate.
Euastrum affine Ralfs, in Annals, vol. xiv. pi. vii. fig. 3.
Hab. In peat pools near Dolgelly: Air. Ralfs. High
Beech : A. H. H. Aberdeen; Dr. Dickie.
Fronds about as large as those of Euastrum Didelta ; the
segments somewhat resemble a decanter in fo rm ; the base
is broad and infiated, and contracted upwards into a wide n e c k ;
the terminal notch is deep but not gaping; the body of the
segment is broadly emarginate on each side ; all the lobes or
projections are rounded and the sinuses shallow.
The var. fl is probably distinct.
6. E uastrum gemmatum Ralfs.
Plate XCI. Fig. 6.
Char. Frond rather more than twice as long as broad. Segments
in front view scarcely emarginate at their extremities,
laterally twice so; in transverse view eight-lohed,
longer than broad ; and in end view four-lobed.
fl Terminal lobe emarginate at each side.
Cosmarium gemmatum Breb., Menegh. 1. c. p. 221. E uastrum
gemmatum Ralfs, Ann. vol. xiv. p. 191. pi. vii.
fig. 4 .; Jenner, in Flor. Tunbridge Wells, p. 198.
Hab. Near Dolgelly: Air. Ralfs. Scrubbs, Colebrook
Park, and on Ashdown Forest, in the great bog near
Forest R ow : Mr. Jenner.
“ Fronds rather smaller than those of E . Didelta, nearly
three times as long as hroad. Each segment consists of a broad
basal portion which is somewhat quadrilateral and emarginate
at each side, and suddenly contracted to form the very short
n eck ; the terminal lobe has each side elongated and rounded
entire in a and slightly emarginated in fl-, the terminal
notch is very obscure. The transverse view is twice as long
as hroad, with two rounded projections at each end, and three
on each side, and a small central opening at the original
junction-point of the segments.” — Ralfs.
7. E uastrum circulare Hass.
Plate X C . Fig. 5.
Char. Frond about twice as long as broad, small, smooth;
each segment anteriorly occupied with seven tubercles, five
at the basal, and tioo at the distal extremity, fo u r o f the
fiv e basal tubercles disposed in a h a lf circle around thefifth.
Hab. High Beech: A. H. H.
A very distinct little species.
b. Segments with acute angles, sometimes prolonged into spinous
processes not generally tuberculated.
8. E uastrum rostratum Ralfs.
Plate XCI. Fig. 8.
Char. Basal lobes o f the segments broad and emarginate.
Terminal lobe with a curved acute spine-like process on
each side.
Euastrum rostratum Ralfs, in Annals, vol. xiv. pi. vii. f. 5.
Hab. In freshwater pools near Dolgelly: Mr. Ralfs.
“ Frond very minute, about twice as long as hroad; segments
obscurely three-lobed, or rather with a broad base,
which is emarginate on each side, and then contracted into a
broad short neck, connecting it with the terminal lobe. The
terminal portion has on each side a curved subacute tubercle
or process, somewhat like a beak; the end of the lobe is
prominent, generally angular, with a deep rounded terminal
notch.”