I 



PLANT LIFE IN PONDS & STREAMS 



rounds itself off, becomes fringed with innumerable 

 little lashing whips and escapes from a pore at the 

 tip of the cell in which it was formed. This little 

 organism swims about for a time in the water, for 

 Vaucheria only increases in this manner when it is 

 under water, at length it comes to rest and forms 

 a new plant. 



Closely related to Vaucheria, but not quite so 

 common, is the curious little plant known as 

 Botrydium Granulatum. Like our previous ex- 

 ample, it is a one-celled plant and herein lies its 

 interest. When find a specimen growing by a pond, 

 we shall notice a green bladderlike portion, not more 

 than J inch in diameter, which projects above the 

 ground. Below ground, if we pick the soil away 

 carefully we may observe a number of colourless, 

 branched structures which do duty for roots. The 

 bladder and underground portions are hollow, being 

 lined in the case of the former, with a network of 

 chlorophyll beautiful to observe under the micro- 

 scope. ! 



Botrydium usually increases by buds which form | 

 on the green bladder, break away and grow into i 

 new plants. Should the level of the water in the [ 

 pond rise, and the little plant become submerged, i 

 it splits up into a number of small bodies, each ! 

 provided with a minute whip-like organ, with which ] 

 they swim rapidly ashore where they develop into h 

 new plants. In dry weather the plant forms a li 

 number of little cells each one surrounded by a firm 

 cell wall. When moisture comes again these little 



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