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AQUATIC PLANTS 



oxygenator. Of a pleasing shade of light green, it makes a contrast- 

 ing group among other plants in a large aquarium, but it shows to 

 best advantage in a small aquarium by itself. It grows from 3 to 8 

 inches and is native to ponds in the Middle Atlantic and Southern 

 States. 



POTAMOGETON 



In strong contrast to the foregoing dainty plants is Potamogeton 

 densus, or pondweed. As will be seen from illustration, these leaves 

 are broad and robust. In color they are a bright green. This variety 

 is said to be of European origin, but is now common in ponds in the 

 United States. If established in soil in flat pots it flourishes in a 

 well-lighted aquarium. Pieces collected from the wild may be intro- 

 duced by fastening into the sand. They present a very attractive 

 appearance and will last for quite a time, but should only be regarded 



Fig. 171. Potamogeton densus 

 (Half she) 



Fig. 172. Nitella gracilis 

 (Two-thirds size) 



