248 FISH CULTURE 



appearance. It has long strap-like leaves, 

 springing from a nearly common base, almost 

 like the leaves of a bulb, and is especially de- 

 sirable for a small aquarium. The Ludwigia 

 Mulerttii is called a submerged plant, but 

 while its greatest growth is beneath the sur- 

 face, it does push its head above the water and 

 sometimes for several inches. It is exceed- 

 ingly valuable for its oxygen-giving qualities, 

 and is one of the prettiest of the sub-aquatic 

 plants. It has small ovate leaves, having the 

 upper part green and the under-side a dark 

 rose pink. It is unlike any other aquatic plant 

 and grows in thick bunches. 



Eel-grass (Vallisneria spiralis) ought by all 

 means to be placed on the list of sub-aquatic 

 plants for the aquarium. It has the male and 

 female flowers on separate plants; the male 

 flowers are borne on straight short stalks, 

 while the female blossoms are on a long spiral 

 stalk. Both open and mature their flowers on 

 or above the surface. 



A favourite aquatic plant with most aquar- 

 ists, and one found in nearly every store deal- 

 ing with goldfish and aquarium supplies, is the 



