232 THE VEGETABLE WORLD. 
there for some time; then finally they become quite immovable, 
and attach themselves in all their length upon the 
spore. Their body loses its form; it is no longer 
a mere mucous drop, of which a part seems to 
be absorbed. by the spore. The primordeal spore, 
now fecundated, soon becomes covered with a true 
eSphosropleas cellular membrane, as represented in Fig. 501.” 
When these spores are prepared to germinate, their contents are 
subjected to many modifications. They become granulated, 
assuming a sombre tint of reddish brown, and e transparent 
circle shows itself in the centre. The reddish matter frequently 
‘ assumes a greenish tint before germination. This change ° 
a b c 
Fig. 302. Spores of Sphzroplea in course of germination. 
colour proceeds slowly and step by step from the exterior of the 
spore towards the centre of its cavity, and the plastic contents 
finally separate, first into two, then into four, and ultimately inte 
a much greater number of parts (Fig. 302, a, 4, c), which rupture 
their double envelopes and spread themselves freely in the wate? 
like so many zoospores. 
The form of these zoospores is as uncertain as their size and» 
colour. During more than an hour these corpuscles, farnished 
with two cilia to their beak, agitate themselves by a slow jerking 
movement, interrupted from time to time with long pauses, ant 
it almost seems as if they had lost their power of movement 
when, after many hours of immobility, they suddenly resume their 
motion. 
When these zoospores begin to germinate they elongate themselves 
more and more, in a spindle-like form, swelling in the middle, 
as in Fig. 303, a, b,c, d,e, f. In a short time the little plant, 
hitherto formed of a single cell, separates into two equal com- 
partments; then, successively, into a great number of cells, at the 
cost of, and in proportion to their size, becoming finally a yours 
Spheeroplea. 
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