every lacinia is drawn out at the apex into tendrils, and the depauperated
lamina very much cut into narrow, jagged processes. Tubercles solitary,
either seated on the nerves of the leaf, or borne on little leaflets rising from
the nerve, depressed, containing a tuft of beaded filaments, finally resolved
into spores, Tetraspores in oblong or linear marginal sori, formed at the
apices of the lateral nerves, often confined to the slender, marginal processes.
Colour, a beautiful purplish crimson or lake. In drying, the frond adheres
to paper.
I
la
Next to I), sanguinea (Tab. CLI.) this, when well grown, and
of large size, is one of the handsomest of the genus. Our plate
represents the frond in rather a young state, a specimen having
been chosen for figuring which exhibits the changes that take
place in form during the growth of the frond. At first the plant
consists of a simple, penninerved leaf sinuated at the margins.
The sinuosities gradually deepen into lateral lobes ; and these
lobes, as is shown in the lower part of the figure, deepen into
branches, or new fronds, at first sinuous, then lobed and at length
divided like the fronds from which they grow. Thus, eventually, a
much branched and leafy frond results from the original leaf, by
regular growth and subdivision of the margin. When any vigorous
part is wounded, an irregular, proliferous growth likewise
takes place, new leaflets springing from any part of the midrib.
Sometimes the margin is much laciniated.
B. sinuosa is abundant throughout the Northern Atlantic. In
the Southern Ocean it is represented by B. guercifolia and B.
Lgallii, two very beautiful species which resemble it closely in
form and mode of growth, but which are essentially different.
Fig. 1. Ayoungand vigorous frond of D e l e s s e r ia SINUOSA. 3. Leaf from an old
frond, of the cut variety, with sori of tetraspores in the marginal lobes:—
both of the natural size. 3. Marginal lobe with tubercle. 4. Section of
the tubercle. 5. Strings of spores, from the same. 6. Marginal lobe,
with sorus, formed out of the apex of the nerve. 7. Tetraspore. 8. Portion
of the surface:— all mag