182 AQUATIC PLANTS 



CABOMBA 



Commercially there is no doubt Cabomba is the leading aquatic 

 plant. Its finely-cut, fan-like, bright green leaves make a very good 

 first impression, although it does not live so well in the aquarium. 

 It is brittle and the fishes if active soon pick it to shreds. Even 

 though this does not occur, it becomes long, spindly, and degenerate. 

 Enormous quantities are gathered from ponds, some of them pur- 

 posely planted, from Maryland to North Carolina. 



The plant under natural conditions is a good producer of oxygen, 

 but in the aquarium its activity in this respect is doubtful. 



Cabomba caroliniaiia is the species usually sold in bunches in pet 

 shops. It is well known as Washington Grass, Fanwort, and Water- 

 shield. In habit it is purely aquatic and propagates mainly by branch- 

 ing. The stems in nature attain a length of several feet. 



Cabomba roscafoUa is a species whose principal distinguishing char- 

 acteristic consists of a distinct reddish hue on the stems and lower 

 sides of the leaves. It, too, is a handsome plant when first introduced. 



ANACHARIS 



Known to American aquarists as Anacharis and in Europe as 

 Elodea, it is also popularly called Ditchmoss, Water Pest, Water 

 Thyme, and Babbington's Curse. Some of the rather uncompli- 

 mentarj' titles are due to a characteristic which, at least in the aqua- 

 rium, should be considered a favorable point, that is, rapid growth. 

 It may generally be taken for granted that if an aquatic plant is thriv- 

 ing it is doing good work for the aquarium. In form it is moss-like, 

 the leaves growing on a fragile stem, the entire plant being complete- 

 ly submerged at all periods. Several species are distributed through- 

 out the United States and Southern Canada. A cultivated variety, 

 probably derived from A. canadensis, is considerably larger than the 

 common local specimens to be found. The closeness of the leaves 

 together depends upon the strength of light in which the plant is 

 kept, the difference being so pronounced that sections of the same 

 plant divided and kept in strong and weak light conditions will soon 

 appear so different as to be scarcely recognizable as the same stock. 

 The plant grows several feet in length, sending off occasional shoots 

 and a few roots at random that reach down into the soil. In the 

 aquarium it is best to only retain from 6 to 15 inches of the newer 

 growth, cutting away the old ends, rebunching and replanting. Plant- 

 ing is a matter of little concern to Anacharis. In a well-lighted aqua- 



