AQUATIC PLANTS OF FRESHWATER 



assigning the long-leaved varieties of C. lanceolata with less crinkled leaves 

 to C. gramin<£. This is not essential to the aquariist. The author illus- 

 trates the species as he recognizes them. It is a variable genus some- 

 times difficult of identification. 



WATERCRESSES 



The Family of Roripa or Watercresses contain about 25 species, 

 most abundant in the North temperate zone, of which eleven are native to 

 North America. Of these the species generally distributed in the East- 

 ern and Middle States are: — 



Roripa palustris {Umn.) Nasturtium terrestre(K. Br.)or Marsh or Yellow 

 Watercress, an erect, branching, glabrous plant having the lower leaves 

 petioled and the upper leaves nearly sessile, with yellow flowers and 

 linear-oblong fruit pods. Flowers May to August. Found in swampy 

 localities throughout entire North America, except the extreme north. 



Roripa sylvestris (Linn.) N. syhestris (A. Br.) or Creeping Yellow 

 Watercress has a creeping stem rooting at the nodules, with ascending 

 branches, pinnately divided and toothed leaves and yellow flowers. Found 

 in low ground and wet places from Massachusetts to Virginia and Ohio. 



Roripa nasturtium (Linn.) N. officinale (A. Br.)or Watercress, Fountain- 

 cress, the edible Watercress, has branched floating and creeping stems 

 rooting from the nodules, with odd-pinnate, ovate leaves, and white flowers, 

 and may be found in almost every coldwater brook of North America. 

 Many cultivated varieties have been produced from this species. 



Another species is Roripa hispida, or Bristly Yellow Watercress which 

 is more seldom met with. It grows on the borders of sluggish streams 

 and ponds. 



Of these, Fountaincress and the creeping Yellow Watercress thrive 

 fairly well submerged in the aquarium and all the species make ornate 

 plants for the aqua-terrarium. 



Closely related to the cresses is another very desirable plant which 

 thrives in the aquarium, the generally introduced Moneywort. 



Lysimachia nummularia (Linn.) or Moneywort, Creeping Loosestrife, 

 also known as Creeping Jenny and Herb-twopence, is a border plant that 

 overhangs the water and develops roots which take their sustenance 

 from the water. It has a glabrous, creeping stem, rooting at the nodules, 

 with opposite, broadly ovate leaves, obtuse at both ends and solitary yellow 

 flowers. This plant thrives satisfactorily in the aquarium, either rooted in 

 soil or in pebbles; and may be found in moist and wet places from New- 

 foundland to New Jersey, west to Indiana; and to be had of florists. It 

 is a fairly good oxygenator and a fine foliage plant in the aquarium where 



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