PLANT LIFE IN PONDS & STREAMS 



cells give rise to structures which will grow into new 

 plants. 



Surpassing even Drapernalda Glomerata in point 

 of beauty, is the *' water-net," Hydrodictyon Reti- 

 culatum, but it is not nearly so common, being con- 

 fined to ponds in the South and Midlands. When 

 full grown it hardly comes under the heading of 

 a microscopic object, for it may measure as much 

 as six inches in length. This remarkable pond 

 plant consists of an open network of green filaments. 

 Apart from its striking appearance the most remark- 

 able thing about the " water net " is its rapid 

 growth. Carpenter, a noted microscopist says : — 

 " The original cells of which the net is composed 

 measure one-two thousand five hundredth part of an 

 inch in length but in a few hours they grow to one- 

 twelfth of an inch or | of an inch in length. 

 We often hear people remark that they can see 

 plants grow, but their statements are not literally 

 true; in the case of the " water net " it is actually 

 possible to see the growth. 



By the side of our pond we shall probably observe 

 some masses of a bluish-green jelly-like substance. 

 It is uninteresting-looking material for the micro- 

 scope, but we must not pass it by. The blue-green 

 jelly encloses a plant called Nostoc, which resembles 

 nothing so much as a necklace of beads ; this we can 

 plainly see under a low magnification. We shall 

 observe that the plant is twisted spirally within its 

 covering and also that most of the cells, which we 

 have compared to beads, are similar to one another 



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