CRYPTOGAMS. 
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no differentiation of root, stem and leaves. In the 
simplest form the thallus consists of a single cell, but 
in the higher forms there is generally more or less 
differentiation in the cells. 
I. ALG JE. 
In a general way the Algje are distinguished as 
fresh-water algse and salt-water algce. They are also 
divided according to their color, there being green algae, 
blue-green algae, brown algae and red algae. In tbe last 
three tbe color of tbe chloroplastid is more or less 
masked or modified by the presence of coloring sub- 
stances which serve to distinguish these groups. 
The outer morphology of the algae appears to be 
rather simple. They may consist of a single row of 
cells placed end to end, forming thread-like masses, as 
in Lyngbya (called mermaid hair), or cord-like masses, 
as in Chorda. In some cases the thread-like filaments 
may branch, as in Griffithsia. The same may be said 
of some of the algae which are made up of a large 
number of cells placed side by side, as Ceramium and 
Dasya. In some cases the thallus is flattened, as in 
Chondrus, Laminaria and Rlxodymenia. In other cases 
the cells of the plant are differentiated to such an 
extent that parts are developed that look like root, 
“ hold fast ; ” stem, “ stipe ; ” and leaf, “ blade,” as in 
Laminaria. In still other cases incrustations of cal- 
cium carbonate are produced, as in Melobesia and 
Corallina. 
Reproduction in the algte may be either sexual or 
non-sexual. Of tbe former, three distinct kinds are 
distinguished, viz.: (1) The conjugation of two cells 
that look essentially alike ; (2) the conjugation of two 
cells that may be distinguished one from the other, 
and to which the terms male and female are 
