ALGAE. 
Most of the species of this extensive natural order 
are aquatic and sub-pellucid, and many of them float 
in the water unattached. Their colours for the 
most part are different shades of green, brown, or 
red—the fructification is various, in some of the 
species the sporules or seeds are scattered thro’ the 
substance of the frond—in others they are enclosed 
in tubercles or processes formed from a continuation 
of the frond—and in some the mode of propagation 
is by Gemme in a viviparous manner. 
A. Fronds articulated, 
DIVISION 1. CHETOPHOROIDER. 
Plants with gelatinous pellucid fronds enclosing 
beaded filaments—which (for the most part) contain 
the fructification. 
NOSTOC. 
An olivaceous bullate frond—fi led with moniliform 
simple curved filaments, 
1, N, Communes. E, Bot. t.461, (TREMELLA 
: N 
