WATEE-PLANTS. 



81 



purple flowers grow in a bunch upon the top of a long and 

 circular stem. This plant is found in ponds and slowly -running 

 rivers, and blossoms from 

 June to September. The 

 Flowering Rush will 

 grow very weU in an 

 aquarium if a small plant 

 (having its tuberous root) 

 is placed in a pot con- 

 taining rich garden 

 mould, covered with 

 plenty of well-washed 

 gravel. 



The Great Water Plan- 

 tain {Alisma Plantago) 

 (Pig. 60) is a very good 

 weed indeed for the 

 aquarium. Its leaves are 

 of two different shapes : 

 those which grow above 

 the water are of a bright 

 green colour, and some- 

 thing like those of the 

 Common Plantain, while 

 those which remain en- 

 tirely under water are 

 long and narrow. The 

 Hlac-coloured flowers 

 grow on long three-sided 

 stalks, which rise some 

 distance above the sur- 

 face. This plant is more 

 or less common in ponds 

 and ditches all over 

 England. It can easily 

 be cultivated in the aquarium, where it is both ornamental and 

 useful. There are very few plants, I think, which so soon 

 begin to grow after having been introduced in the tank. SmaU 



G 



Fig. 60. Great Water Plantain 

 (Alisma Plantago). 



