CALIFORNIA PLANTS IN THEIR HOMES 

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Fig. 1. WATER-NET Hydyodictyon. 

 \. Colony, x 5. 2. Tip of net, x 15. 3. Single mesh, x 40. 



I. One cell, x 75. 



meshes are large; but the large nets are easily torn, and 

 are likely to be found in ragged bits. There are usually 

 plenty of smaller nets ; if you have sharp eyes you may 

 find some not more than one-eighth of an inch long. 

 Drawing No. 2 is one end of one of these tiny nets as it 

 looks under the microscope, and No. 3 is one of the meshes 

 still more enlarged. Take the coarsest net you have, and 

 find out how many sides the meshes have. How long is 

 the longest side you can find ? 



No. 4 is a drawing of one side of a mesh under the 

 microscope. So we see that each side of any mesh is itself 

 a little closed bag or sac filled with something. This sac 

 with its contents is called a cell; the sac is transparent, and 

 is called the cell wall. The jelly-like substance within 

 seems to be green, and there are grains in it, some very 

 small, others larger. After water-net has been kept in 

 alcohol for a day or so, the alcohol becomes green and the 

 net is left colorless, but otherwise the cells look just as they 

 did before. This coloring matter, which is dissolved by 

 the alcohol, is a very important part of plants, so important 



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