Bn 2 Ss packing and Physiological Botany, ee 
| after fertilisation, with a membrane of cellulose, cre. becomes 
the oospore or embryo. This embryo assumes the form of 
a resting-spore, which does not germinate at once, but 1 is set 
Fic. 385.—I. A, Filament of 2dogonium ciliatum: x cells 
which produce the swarmspores; og oogonium with 
dwarf-male 7 ; B, oogonium at the moment of i impregna- 
vie tion; 0 oosphere : gz antherozoid in the act of entering ; 
m dwarf-male ; Cc, O. gemilliparum: piece of a filament 
in which the swarmspores z are being formed, from which 
the dwarf-males are produced (x 250). II. Swarmspores 
of Edogonium: A, before escape from their mother-cell ; 
B, in Na act of escaping ; C, when set free. (After Prings- 
heim. 
free when the Alga itself decays, sinks to . 
the ground, remains dormant through the 
isi\ winter, and germinates in the spring. In 
eatin (Fig. 385) the oogonium is acell of the filament 
itself. The multicellular antheridium or ‘Dwarf Maie’ is 
formed from a peculiar swarmspore [androspore| which 
attaches itself to the oogonium. Only a single antherozoid — 
is formed in each cell of the antheridium, which escapes 
