; 
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z 
re 
a 
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i> a J t i “or a Biot on a 
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aS oe Cee ee ae < . = r 
eee oe ee eee 5 ie iy , 4 
¥ ane Xe? = > . / ; 
r 
Special Morphology and Classification, 25% 
single reproductive cell, as in Pandorina and Ulothrix. 
‘This last form of conjugation constitutes a connecting link 
between the modes of reproduction by swarmspores and by 
oospores. Those processes of impregnation are more com- 
plicated in which the two cells which share in the produc- 
tion of the embryo are unlike. The fertilising [male] body 
is in these cases termed a sfermatozoid, antherozotd, or 
_———__ 
Fic. 382.—Tetra- Fic. 383.—Conjuga- Fic. 384.—Vaucheria hamata: a oogo- 
spores of Coral- tion of CJlosterium nium open at the apex; 6 antheridium 
lina cupressina, Lunula, a Desmid also open, from which the antherozoids 
enclosedinthecon- (greatly magnified). | areescaping; c parent filament ; dsingle 
ceptacle cut open. antherozoids more strongly magnified: 
(a-c X 400.) 
Sperm-cell ; the mass of protoplasm which has to be fer- 
tilised [female cell], an vosphere or Germ-cell. The latter 
are many (often several hundred) times larger than the 
former. The antherozoids are first fornied in a cell which ~ 
is called an enthertdium, and the oosphere is the result of 
the contraction of the protoplasm of a special cell termed 
the oogonium. In Vaucheria, Fig. 384, a number of elon- 
gated antherozoids are formed in the antheridia, here called 
‘horns ;’ these penetrate into the oogonium through an 
opening formed in its cell-wall at the period of its maturity, - 
and finally reach the oosphere. The latter clothes itself, 
