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CLASS CRYPTO GAMIA. 
The Fccus giganteus is said to have a frond of immense 
length ; from whence its specific name signifying gigantic. 
You are here presented ( Fig. 50.) with a delineation of three 
kinds of Fuci. (a) Fucus nodosus (knobbed fucus) this has forked 
fronds. The knobs which appear in the fronds, are air-bladders, 
which render it peculiarly buoyant upon the water. This is 
often more than six fjpet long. (b.) Fucus vesiculosus (bladder 
fucus) here the air-bladders are mostly axillary, and at the sides 
of the mid-rib. It varies in length from one to four feet. On 
account of its mucilaginous property it forms a good manure ; 
and in some of the countries of Lapland it is boiled with meal, 
and given for food to cattle, (c,) Fucus serratus, has a beautiful 
serrate or notched frond. 
The Fuci, on burning, afford an impure soda called Kelp. 
Lichenes — or lichens. 
The 5 th order contains the Lichens ; these are various in 
texture, form, and colour ; they are leathery, woody, leaf-like, 
white, yellow, green, and black. When wet, they often appear 
like green herbage ; some appear on stones or old fences and 
buildings ; others with strong, green filaments, are suspended 
from branches of trees and improperly called mosses. The 
fruit of the lichen consists of tubercles, or saucer-like bodies in 
which the seeds are contained ; this may be seen in the follow- 
ing delineation. (Fig. 51.) (a) represents a lichen of a leaf-like 
Delineation of three kinds of Fuci — Kelp — Lichens — Of vhat the fruit 
consists. 
