BY THE SEASIDE— PLANT LIFE 



pear shaped swellings occur on the threads of the 

 sea- weed. If we are either fortunate or exception- 

 ally patient we may chance to be examining one of 

 these swellings under the microscope at the moment 

 when it bursts and sets free its contents. Should 

 we have this good fortune we must hasten to 

 magnify more highly the zoospores which have 

 escaped from the pear shaped spore case. Here we 

 may add the caution that we shall only witness the 

 bursting of the spore case if we examine our speci- 

 men in sea water; we should require more than 

 the patience of Job to watch for its bursting in the 

 dry state, for it will never come to pass. 



A careful study of a zoospore will show that it 

 swims in a peculiar manner. One of the little whips 

 is directed forwards, the other trails behind. After 

 a short period of activity the zoospore comes to 

 rest, loses all means of propulsion, germinates and 

 grows into a new Ectocarpus plant. 



Sometimes this Algse reaches a low ebb of vitality, 

 it requires a new lease of life as it were, when this 

 state is reached another form of increase takes place. 

 The events in this case may also be witnessed under 

 the microscope. From very similar spore cases a 

 number of zoospores are liberated and for a time 

 they swim about freely. If now we watch carefully 

 we shall notice that one of the active little bodies 

 comes to rest and that the others lose no time in 

 swarming round it. One of these swarming zoo- 

 spores fuses with the individual which first ceased 

 swimming about, with the result that a much larger, 



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