226 ESSENTIALS OF BOTANY 
felt-like masses which it forms. It must not be confused 
with moss protonema (Fig. 199) which also grows on 
damp earth. The protonema has many cross-partitions in 
the filaments (often oblique in position) and lacks other 
Fic. 157. Vaucheria synandra. 
A, a filament with archegonia and antheridia (considerably magni- 
fied) ; B, part of same much more highly magnified; 0, odgonium; 
a, antheridium; C, a later stage of B; D, end of a filament with 
a zodspore, Z, escaping (highly magnified). 
characteristics shown in Fig. 157, 4. It will also usually 
be found to be developing young moss plants. 
290. Gross Structure. — Place in a white saucer or a watch glass 
with very little water some bits of earth on which Vaucheria is grow- 
ing. Have other specimens growing in water in a sunny place, 
where they should have remained undisturbed for a week or more, 
