îi
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* * Frond plane or compressed, without a midrib.
4. F u cu s NODOSUS.
Frond compressed without a midrib, vesicles solitary at remote intervals,
receptacles lateral somewhat pear-shaped distichous stalked.
Vucus nodosus, L liu i. S p . P I . p . 1028. S t a c k h . N e r . B r i t . t. 10. T u r n . S y n . F u c . p . 262.
H i s t . F u c . t. 91. Sm . E n g . B o t. t . 670. L am o u r . E s s a i, p . 19. A g . S p . A lg . v . 1. p . 85.
S y s t. A lg . p . 275. G re v . F I. E d in . p . 284. S p r e n g . S p . P I . y . 4 . 316.
Halidrys nodosa, L y n g b . H y d ro p h . D a n . p . 37. t . 8. G a ill. in . D i e t . S c . N a t . v . 4. p . 316.
H a b . Sea shores. Perennial. Winter and spring. Common.
Root a hard conical disk. Fronds tufted, two to six feet long, two
or three lines wide, linear, a few times dichotomous, the divisions irregularly
pinnated with spreading branches attenuated at their base
almost to a point and furnished with minute, remote, distichous, teeth :
from the axils of which the receptacles and young branches are produced.
Vesicles from three quarters of an inch to one inch and a half
in length, elliptical or oblong, swelling to three or four times the diameter
of the frond, of which they seem to he inflated portions. Receptacles
arising distichously from the whole of the frond, varying
from spherical to oblong, half an inch to an inch in length, solitary or
several together, of an orange-yellow colour when ripe, suppoi ted upon
a little compressed stalk.
Substance remarkably tough and coriaceous. Colour opake olivaceous
green. In drying, every part, except the ripe receptacles, turns
black, and does not adhere to paper.
Like the other larger Algse, its mode of growth is more or less influenced
by its situation; several varieties might therefore be enumerated
depending for their characters upon size and relative proportion
of the different parts. When growing in deep water the frond is carried
out to a great length, the vesicles are distinct and very large, and
the receptacles mostly towards the extremity. In shallow water, where
the plant is a good deal exposed to the sun, the frond is sometimes
not above a foot long, and crowded with large yellow receptacles in a
very beautiful manner. When injured, the whole frond is capable of
producing new shoots in the utmost profusion. A singular but solitary
specimen, distinguished by linear-lanceolate receptacles, was found
at Dover by Mr Dillwyn, and communicated to Mr Turner, in whose
Historia Fucorum it forms the variety siliquatus.
This species is known in some parts of the kingdom by the name of
Sea-ivhistles, in consequence of the custom which the children have of
converting the vesicles into whistles, by cutting them in a particular
manner. Mr Neill mentions, that, in Orkney, it is called Yellow Tang,
on account of its conspicuous yellow receptacles. In Norway it is
named Knoptang, because of the knob-like vesicles. It is a valuable
species in the making of kelp. Polysiphonia fastigiata {Conferva
polymorpha of British authors) is parasitic upon it, and indeed rarely
to be found elsewhere.
5. F u cu s M a c k a i i .
Frond between compressed and cylindrical almost filiform dichoto—
mous uniform, vesicles elliptical solitary.
Fucus Mackaii', T u r n . H i s t . F u c . t . 52. Sm . E n g . B o t . t . 1 9 2 /. L am o u r . E s s a i, p . 20.
Ag . S p . A lg . V. 1. p . 87-
Fucus nodosus v a r . y Mackaii, A g . S y s t . A lg . p . 275. S p r e n g . S p . P I . v . 4. p . 316.
H a b . Sea shores. Perennial. Cuiinemara, county of Galway, Mr
J- T. Maclcay. Loch Seaforth, Lord Seaforth. Arasaig, Mr Borrer.
Loch Coul and Kyle Scough, Sutherland, Messrs Borrer and Hooker.
Fastern coasts of the Isle of Skye, and head of Loch Duich, Messrs
Hooker and Greville.
Frond six to nine inches long, one to two lines wide, becoming-
narrower towards the extremity where it is filiform and cylindrical,
towards the base and in the broader varieties compressed; dichotomous,
and crowded with branches more or less divaricated at the axils,
and terminating in short obtuse forks. Vesicles scattered, solitary, two
or three lines long, elliptical, wider than the frond in which they are
innate. Receptacles unknown.
Substance coriaceous, when dry hard and horny and semitransparent.
Colour olivaceous green, often tinted with brown or yellow. In drying
it does not become very much darker.
As the fructification of this plant is unknown, some doubt exists
whether it be really a distinct species. Agardh in his last work has
made it nothing more than a variety of F. nodosus, and it is highly
probable that farther information may prove him to be correct. Perhaps
the very circumstance of the plant having never been observed in
fructification, though produced in inconceivable abundance, is in favour
of its being a variety. I once saw the sea-beach in the Isle of Skye
covered with it to the extent of an acre in one place, and presenting a
most deceitful surface ; for the sea had left the whole mass apparently
growing in an erect manner, bristled with the tops of the filiform
branches, and completely concealing a dangerous muddy shore that lay
J I-»”