B O T 
ters of all the plants in this order, are fully investigated 
and explained under their generic names in the body of 
this work ; but we Shall neverthelefs State, in this place, 
tlie feveral conjectures relative to the mode of propaga¬ 
tion in thefe plants, bccauSe it is an enquiry eflential to 
the knowledge of Botany. 
The foliage or frond of the Lichen, varies confiderably 
in different plants. In fome the Substance is foft and flelhy ; 
in others it is hard and tough, like leather: in fome again 
it is membranaceous or fibrous ; jelly-like, or horn-like ; 
or refembling calcareous earth ; and in fome it even pof- 
fefles irritability, or an appearance of fenfation. In the 
Lichen citiaris, the fringes at the extremities deftined to 
take root, and the downy matter on the furface, have no¬ 
thing to do with the parts of fructification. Thefe are to 
be found in the concave faucers above-mentioned, or in 
convex targets or warts, either on the fame, or on a dif¬ 
ferent plant. They both arife from a kind of knot on the 
under furface of the frond. The warts change to a brown, 
and then to a black colour, at the top ; but, before they 
become brown, a perpendicular feCtion through one of 
them, difcovers a Single or double cell buried in the ten¬ 
der pulp of the plant, and filled with a granulated fub- 
ftancc. Whenever the top of this wart or tubercle turns 
black, the granulated mafs has then efcaped through it, 
and only a kind of jelly remains in the cells ; which, how¬ 
ever, foon vanishes, whilst the whole tubercle becomes 
black and hard. This procefs is performed in a very Short 
time. The rising particle, which is deftined to form a 
concave Saucer, becomes hollow' and green at the top, 
through which, if we make a perpendicular Section, we 
find fibres radiating from its centre, and forming a Semi¬ 
circle, bounded by a more opake line. As this continues 
growing, the faucer becomes larger, and more and more 
open. Its cavity is at firSl reddiSh, gradually becoming 
darker. At length it becomes a perfeCt faucer, either fit¬ 
ting, or Supported on a Short footflalk ; its border is either 
fcolloped or entire, black within when moift, and greyiSh 
when dry. If we now cut the faucer through, and exa¬ 
mine a vertical feCtion of it in a little water, we Shall find 
immediately under the black cruft at top, the feeds dif- 
pofed in Straight perpendicular columns. When very high¬ 
ly magnified, thefe feeds appear egg-Shaped, but marked 
with a diftinCt groove tranfverfely. No unprejudiced per- 
fon can therefore doubt but that the warts with the black 
tops are the male, and the Saucers the female flowers. 
The faucers, in all the fpecies of Lichen, refemble the 
above in the mode of flowering, and in the Same disposi¬ 
tion of their fruit. The male flowers are alfo Similar, 
whether contained like thofe of the Lichen ciliaris in the 
fubftance of the plant, or as in others, on its furface. In 
fome fpecies, they are found on the extremities of the 
branches ; in others on the edges ; and in others again on 
the under furface, where they Sometimes form circles foine- 
what refembling faucers. The Natural Characters, and Sub¬ 
divisions of the Lichens, are therefore as follow : Male .— 
Scattered wart-like fubftances. Female. —Smooth faucers 
er tubercles, in which the feeds are imbedded.— Subdivi- 
fiens. i. Subftance like powder. 2. Cruftaceous, granu¬ 
lated; with black lines ; with tubercles; with Saucers ; 
er with both tubercles and faucers. 3. Cruftaceous, ti¬ 
led, fpreading, flat, fixed down to the fubftance on which 
it grows, 4. Somewhat cruftaceous, leaf-like, tiled, loofe. 
5. Somewhat cruftaceous; bearingcups Shaped like a jelly- 
glafs. 6. Somewhat cruftaceous ; Shrub-like ; (hooting 
into branches refembling a Shrub, or branches of coral. 
7. Somewhat cruftaceous ; thread-like. 8. Leafy, her¬ 
baceous. 9. Rootfingle; in the centre of the plant. 10. 
Foliage tough, like leather. ix. Gelatinous; foliage, 
when frefh and moift, like jelly. 
Exampi.es for Investigation. 
The delineations we Shall .give of the fructifications of 
this very obfeure order of plants, are taken from the new 
edition ef Dr. Withering’s excellent arrangement; the 
ANY. • 2S3 
value of which can only be estimated by their correctness, 
and Strict conformity with nature. Fig. 15, is a frond of 
the Lichen ciliaris, Strongly magnified to (hew the parts 
distinctly ; a a, the male warts or flowers in the fubftance 
of the plant; h, the female flower ; cr, the fringes which 
expand from the ends of the branches, and (trike root ; 
d d, younger Shoots, which have not yet given out their 
fibres or fringe. Fig. 16, a part of the crenulated lichen, 
to Shew the fructifications ; e, the faucers, red ruli-colour, 
varying in Size, border the fame, very finely fcolloped ; 
cruft grey \f four of the fructifications confiderably mag¬ 
nified. Thefe lichens aie found on rocks and trees, and 
upon the large flints on the molt elevated parts of the back 
of the llle of Wight. Fig. 17, part of the tricoloured lichen, 
a very beautiful fpecies; the faucers, g, orange-coloured, 
border pale brown; cruft dull green; the faucers very 
minute, and deeply hollowed; h, four of the faucers mag¬ 
nified, to (hew the elegance of their Structure ; i, a Single 
faucer taken from the plant and magnified.—See the ar¬ 
ticle Lichen. 
The lichens, though generally looked upon as unworthy 
of notice, are of Some confequence in the oeconomy of na¬ 
ture, and afford the firft foundation for vegetation. The 
cruftaceous kinds fix upon the bareft rocks, and are nou¬ 
rished by fuel) Slender Supplies as the air and the rains aS- 
ford them. When thefe die, they are converted into a 
very fine earth, in which the tiled lichens find nourish¬ 
ment, and when thefe putrify, and fall to duff, various 
modes, as the Bryum, 1 -Sypnum, &c. occupy their place ; 
and in length of time, when thefe peiifh i'fi their turn, there 
is a Sufficiency of foil, in which other plants; and even trees, 
take root. This procefs of nature is Sufficiently apparent 
upon the Smooth and barren rocks near the lea Shore. Many 
of the lichens alfo afford a grateful food to goats; and the 
rein-deer, which conftitutes the whole ceconomy of the 
Laplanders, and Supports many thoufand inhabitants, lives 
upon one of the fpecies of thele humble plants. Many of 
them afford colours for dying. One of them, brought 
from the Canary islands, viz. the orchel, or ai'gol, makes 
a very considerable article of traffic. It is not improbable, 
that Some of the Species growing in our own island, may 
afford very beautiful and ufeful colours; but this matter 
has not been Sufficiently examined. Mr. Hellot gives us 
the following procefs, for discovering whether any of thele 
plants will yield a red or purple colour. “ Put about a 
quarter of an ounce of the plant in queffion into a Small 
glafs ; moiften it well-with equal parts of Strong lime-wa¬ 
ter, and Spirit of fal ammoniac; or the Spirit of Sal ammo¬ 
niac made with quick lime will do, without lime-water. 
Tie a wet biadder clofe over the top of the veil'd, and let 
it (land three or four days. If any colour is likely to be 
obtained, the Small quantity of liquor in the glafs will be 
of a deep crimfon red; and the plant will retain the fame 
colour when the liquor is all dried up. If neither the 
liquor nor the plant have taken any colour, it is needleis 
to make further trials on that Species.” 
Fuci, or Sea Weeds. 
No fubjedl in botany, perhaps, has been fo little attend¬ 
ed to as the investigation of marine plants; though from 
their variety and beauty, and the Singularity of their Struc¬ 
ture, it is Surprising that the attention of the ancients was 
never excited by them. Among the moderns, the public 
have now a work of Singular merit to encourage, in the 
“ Nereis Britanhica, or Botanic Description of British Ma¬ 
rine Plants,” by John Stackhoufe, Efq. And alfo a very 
elegant tract, by Major Velley, full of information, on the 
“ Mode of Propagation pecidiar to Sea Plants.” From 
thefe interesting pages we Shall endeavour to furnish the 
young botanist with a pretty-accurate idea of the princi¬ 
ples of fructification in the Fucus. 
“ If we except the history of the fucufes written by 
Gmelin, who, with much ingenuity and experimental 
knowledge, has endeavoured to elucidate the myfterious 
principle by which their propagation is effected ; and the 
3 general 
