98
tliougli not, I conceive, with sufficient precision. His P. glandnlo-
sum ami Lahillardieri differ very decidedly in their fructification. His
P. maxillosum I have never seen: it is, however, considered as a variety
of P. coccineum by Agardh, and the latter is therefore probably
the type and only known species of the genus.
I
I >
1. P l o c a m i u m c o c c i n e u m . Tab. X II.
Plocamium coccbmon, L y n g b . H y d r o p h . D a n . p . 39. t . 9.
Plocamium vulgare, L am o u r . E s s a i, p . 5 0 . G a ill. D i e t . S c . N a t . v . 53. p . 368.
Delesseria coccinea, Ag . S y n . p . x iv . G r e v . F I . E d in . p . 294.
Delesseria Plocamium, A g . S p . A lg . v . 1. p . 180. S y s t . A lg . p . 250.
Fucus Plocamium, G m e l. H is t. F u c . p . 153. t . 16. f . 1. L ig h t f . F I . S c o t. p . 957.
Fucus coccineus, H u d s . F I . A n g l. p . 586. S t a c k h . N e r . B r i t . p . 106. S m . E n g . B o t. 1 . 1242.
T u m . S y n . F u c . p . 291. H i s t . F u c . t. 59.
H a b . In the sea, very common every where. Perennial ? Summer
and autumn.
Root a small disk, accompanied with a mass of entangled fibres.
Fronds numerous, two to twelve inches in lengtli, the main branches commonly
about lialf a line in width, but occasionally broader, and sometimes
much narrower, flexuose, irregularly alternate, patent. All the smaller
branches are "set with uniform ramuli, like the teeth of a comb, and in
a regular distichous order, three or four on one side, and then three or
four on the other ; these produce a second series of three or four short
ramuli from their upper edge, and a third or even fourth occur, each
smaller than the preceding one, similar in number, and always from
the upper or inner edge. This character is sufficient to distinguish
the species from all other Alga. Fructification : 1. dark and spherical
capsules as large, or a little larger than poppy-seed, mostly on some
part of the margin of the smaller branches: 2. transversely parted
granules placed irregularly, or in two longitudinal series, in minute
lanceolate processes, which are single or clustered, and arise from the
margin of the ultimate pectinate ramuli, or even from other parts of the
smaller branches.
Sííisíance more cartilaginous than membranaceous, adhering to paper
in drying. Colour a very beautiful red, between scarlet and crimson.
One of the most charming and symmetrical alga in the world, extremely
common, and a universal favourite. Though liable to vary very
considerably in size and in the proportion of its parts, a single glance
at the beautifully regular and peculiar division of the ultimate branches
is at all times sufficient to distinguish it. I have specimens not above
an inch in height, with the frond almost as fine as a hair, and others
from New Holland, a line in width, and above a foot in length, hut the
admiral)le character above mentioned is equally striking in each.
G e n u s XXVITI. MICROCLADIA. Grev. Tab. X III.
G e n . C h a r . Frond filiform, compressed, subcartilagiiious,
irregularly brancbed, tbe branches distichous. Fruc tification
of two kinds : sessile splierical capsules, accompanied
by an involucre, in the form of several short
ram u li: and ternate granules in the swollen apices of tbe
branches.
O bs. The type of this genus is the Fucus glandulosus of the Bank-
sian Herbarium, and of Mr Dawson Turner; the Delesseria glandulosa
of Agardh. At first sight it appears to be nearly allied to Plocamium
coccineum : but it differs in the capsules, being provided with an
involucre, and essentially in the different structure of the granules,
which are besides confined to the apices of the frond. The structure
of the frond is also different, being reticulated, the interstices dense.
The generic name is derived from two Greek words, and signifies
finely branched.
1. M i c r o c l a d i a g l a n d u l o s a . Tab. X III.
■:|i:
Delesseria glandulosa, A g . S p . A lg . v . 1. p . 192. S y s t . A lg . p . 251.
Fucus glandulosus. H e r b . B a n k s . T u m . H i s t . F u c . t . 38. S m . E n g . B o t. t . 2135.
H a b . In the sea, growing upon other Alga. Annual. Producing
fructification in September and October. Budleigh and Torquay, Mrs
Griffiths.
Root a minute disk. Fronds two to three inches long, and as many
broad, much branched from the very base ; branches one-third of a
line in width, compressed, irregularly given off; the secondary ones
patent, many times divided in an alternate manner, the ultimate ones
very short, forked, rather acute, and mostly incurved like a pair of
forceps. Fructification : I. minute spherical capsules, sessile on the
margin of the branches, and surrounded by an involucre composed of
two to six short incurved processes: 2. ternate granides scattered in
the swollen apices of the branches.
G 2