Fuci. 
. = 
 ALCYO- 
Ex. 
FUCI. 9 
F. cattoides, (¢. 1'71,) brought by Mr Brown from the 
south coast of New Holland; and I’. hypnoides, (t. 173.) 
brought from Kent’s Islands by the same naturalist. 
This last is not 3 for its beauty, but is 
very remarkable for the exterior of the stem being close- 
ly beset with small scales, like some of the fern tribe : 
to this there is nothing analogous among the rest of 
the fuci; the of scales in F. squamulosus 
(Turn. t. 128.) being occasioned merely by the remains 
of old ramuli. The other new species of Caulerpa pub- 
lished ‘by Turner, were brought from the Red Sea 
by Mr Salt, and are likewise very curious. The Cau- 
lerpe appear to be perennials, or at least to endure for 
more than one year. We may remark, that the sea- 
weed of'a fine green colour, described by Humboldt as 
found growing in the sea at the great depth of 192 feet, 
and by him named Fucus vitifolius, belongs to this ge- 
nus. 
The fifth order, Aucyontpex, is characterised by the 
* organization being gelatinous, or like that of a tre- 
mella, of a dirty olive red colour, becoming darker on 
exposure to the air.” The Alcyonidew evidently ap- 
very near to the of the genus Alcy- 
onium ; but neither polypi, nor the habitations of poly- 
pi, are to be observed in them. A transverse section 
of these plants, exhibits al or irregular re- 
tieulations, which diminish in size towards the sides of 
the stem. In a longitudinal section, these reticulations 
lengthened, and form at the exterior a very fine 
cpndariniy. The fructification of this order is conspi- 
cuous enough. It consists of yellowish capsules, situ- 
ated in the epidermis, and full of small black seeds. 
The Alcyonidez have considerable affinity to the genus 
Dani of the Floridez, above described. They de- 
com ee left by the tide on the shore. 
Their texture is so loose, that when once dried and 
they never resume their original form. 
i. The only genus is Alcyonidium: “Capsules containing 
seeds, innate in the fleshy or gelatinous substance of 
the plant.” The principal species is the Ulva diapha- 
na of former writers, (Eng. Bot. t. 263), and which is 
not uncommon on’ our shores. It is remarked by M. 
Lafoy; that, at certain times of the year, the Ulva dia- 
phana is t; but this fact has not been ac- 
curately ascertained, and itis possible that the phospho- 
rescence alluded to, miiy ve sang merely on numbers 
ofa minute shining nereis : ig to the plant, when 
newly cast ashore, or drawn’ from the sea. We have 
frequently observed a brilliant horescent appear- 
ance iced by this cause, in specimens of Fucus 
dentatus, and in various species of Sertularia, recently 
taken from the sea, the phosphorescence being renewed 
upon moving the specimens, or disturbing the minute 
The sixth order, SPoNGODE®, lids this character: “ Or- 
ization ; colour green, tarnishin 
sure to the air.” This order, as published by Lamou- 
roux, consists only of a single genus, which Olivi, a dis- 
tinguished Italian naturalist, proposed in his Zoology of 
the Adriatic oe the namie of Lamarckia. This 
name, however, having been pre-occupied by a genus 
oa — plants, “<p fiocste meer Codium. 
mouroux | x godium, on account of 
the quediamibanarst the + plants which constitute 
the genus, to some’kinds of sponges, and because, like 
them, they imbibe water. It has this character : “ Seeds 
seattered through the substance of the plant, but most 
abundant at the extremities of the filaments which clothe 
its surface.” One of the principal: species is Spongo- 
VOL, X. PART I. 
on expo- . 
dium dichdtomum, the Fucus tomentosus of former 
authors, figured in English Botany, t. 712, and in 7) 
Paci. 
eed 
the History of the Fuci, t. 135. The substance of the yo. .ou- 
plant consists of a collection of interwoven fistular tubes, yous. 
full of a transparent fluid. The surface, as noticed in 
the character, is covered with small capillary filaments, 
which seem to serve for the absorption of water, and 
among which vesicles and capsules are to be looked for. 
These filaments are best observed while the plant re- 
mains in the sea: when it has been withdrawn for 
some time from that element, they nearly disappear. 
The colour is a dark grass green, which becomes paler 
by drying. It may be proper. to add, that the Fucus 
fungosus, found on the coast of Barbary by Desfon- 
taines, and described in the Flora Allantica, is to be 
considered as only a variety of F. tomentosus. Ano- 
ther species of Spongodium is Fucus bursa of our shores, 
( Turn. t. 186.) the Aleyonium bursa of Linneus. | It 
may here be mentioned, that since the publication 
of Lamouroux’s system, Turner has described and fi- 
gured (Hist. Fue. t. 175) a new spongodium, by the 
title of Fucus simpliciusculus, a name which is to be 
understood as applicable only in a relative sense, being 
meant to distinguish it from either the dichotomous ra- 
mification of F. tomentosts, or the spherical shape of F. 
bursa. Instead of having a soft velvety exterior like 
these, it is papillose ; but its internal structure is quite 
similar. Turner remarks, that F. simpliciusculus, in 
external appearance, closely resembles the caulerpe, 
having the same colour, the same glossy surface, and 
the same kind of substance, intermediate between the 
submersed algw and the zoophytes, or even approach- 
ing more to the nature of the latter than of the former. 
The spongodex appear to last more than one year. 
They inhabit places never completely uncovered by the 
tide. They are’nearly allied to the Ulvacee, and might 
perhaps commodiously follow thein. 
In Lamouroux’s arrangement of sea-plants which 
has now been detailed, no fewer than 273 ascertained 
ies are referred to by the author. There are, be- 
sides, near 200 gapeblidied species alluded to by him : 
of 20 of these, figures are given in the Annales, but no 
descriptions ; and when, or in what form, the remain- 
der ate to be brought before the public, does- not ap- 
pear, There are nearly 100 varieties of different spe- 
cies mentioned ; but in no tribe of plants is there great- 
er difficulty in determining the limits between species 
and varieties ; it will be nowise surprizing, therefore, 
if several of these varieties be hereafter established as 
species; and, on the other hand, a few of the species 
degraded to the rank of varieties. Marine plants are not 
only liable to very considerable diversity of form, but, 
as already noticed, it is nearly impossible to cultivate 
them with a view to observe their germination, and 
extremely difficult even to watch their progress, on their 
native submarine rocks, from infancy to maturity. Of 
the ascertained species, 148 are found on the shores of 
France, 
In the course of our ample account of Lamour- 
oux’s' arrangement, a number of particulars connected 
with the general history and physiology of these plants 
have been incidentally stated. There remain, however, 
several points deserving of further and separate consi- 
deration, particularly their germination and growth, 
their general structure, and the nature of their fruc- 
tification. 
Notwithstanding the many observations of late in- 
quirers, in no department of natural history does there 
B 
