ft
more or less deeply and repeatedly cleft into numerous dicliotomous, patent
segments, with broad, rounded intervals, and more or less obtuse, often
very obtuse apices. The lower segments are more or less cuneate, the
upper mostly linear, witb a perfectly flat and even, entire margin. Sometimes,
especially iu specimens that bear tubercles, tbe apices arc more or
less erose and jagged. In var. ^. tbe disciform root senc s out very numerous
filiform, branching surculi, from whose sides spring, very irregularly,
simple, or once forked, very narrow fronds, attenuated at tbe apex, and
sometimes produced into long, filamentous cirrbi. Tuhercles globose,
seated on the margin or disc of the uppermost segments, with a wide pellucid
border, and thick cellular pericarp, containing a very convex mass of
angular spores. Tetraspores forming deep red blotches in tbe pale, expanded
apices of tbe segments, cruciate or tripartite. Colour, a fine pinky
red, preserved in drying. Substance membranaceous, somewhat rigid, and
very imperfectly adhering to paper in drying.
This pretty species, though it varies as to the greater or less
division of the frond, generally preserves a tolerably uniform,
flabellate outline, which, taken in connexion with its bright pinky
colour, and rather rigid, crisp substance, sufficiently distinguishes
it from any British species. There are some closely allied forms
in the Southern Ocean, as B. corallina and B. flabelliformis,
which it is sometimes more difficult to separate. Among British
plants the nearest in form is certainly B. membranifolia (Chondrus
membranifolms, Grev.), but this may always be known by the very
different colour, independently of differences in the fructification.
A marked difference exists between specimens which produce
tetraspores, and those that bear tubercles, as may be seen by
comparing our upper and lower figures. The former are invariably
more expanded, with broad and rounded tips ; the latter
more drawn into a stem with shorter and denser segments, and
truncate or abruptly cut tips.
A very remarkable variety, which bears a close resemblance to
the var. /3. of Phyllophora Brodioei, is noticed above under the
name Nicæensis, and represented at fig, 3. This always springs
from decumbent fibres, which often acquire a considerable length.
In the Mediterranean specimens the frond is usually quite simple,
prolonged at the apex into a cirrhous appendage. British specimens
are more commonly forked, and their apices, though attenuate,
seldom produced into a tendril.
Kg. 1. R h o d y m e n i a P a lm e t t a : specimen witb sori of tetraspores in tbe
tips. 2. Specimen bearing tubercles. 3. Yar. /3. :—all o f the natural size.
4. Apex of a segment, witb sorus. B. Cross section of tbe same. 6.
Tetraspores. 7. Apex of a segment, witb tubercles. 8. Section of a
tubercle. 9. Spores ;—all more or It
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