AQUATIC PLANTS OF FRESHWATER 



cavity. It is half-hardy plant introduced from Chili, of most delicate 

 vivid green foliage composed of finely cut leaves. Flowers in July 

 and August. 



Proserpinaca pectinata (Lamm.) and P. pectinacea (T. and G.) or 

 Cut-leaved Mermaid-weed may be found in sandy swamps near the coast 

 from Massachusetts to Florida and west of Louisiana. Flowers June to 

 September. Somewhat similar to the above. As will be seen by the 

 illustration, these plants differ in appearance with Parrot's feather, the so- 

 called Proserpinaca of the aquarium. They are tender-leaved plants and 

 do not usually survive in household aquaria. 



LUDWIGIA 



Of the so-called Swamp Loosestrife, named for the German naturalist 

 Ludwig, there are about 25 aquatic or semi-aquatic species native to warm 

 and temperate regions and abundant in the United States and North 



America; the most generally distributed being the 

 following, of which the popular names indicate 

 the character; and also several introduced species 

 extensively cultivated for the aquarium. They 

 are beautiful foliage plants of most attractive 

 colorings. Those most generally to be obtained 

 are: — Isnardia palustris or Ludwigia palustris, 

 Marsh purslain or False Loosestrife; L. polycarpa, 

 Many-leaved Ludwigia; L. sph^rocarpa. Globe- 

 fruited Ludwigia; L. glandulosa, Cylindric-fruited 

 Ludwigia; L. linearis, Linear-leaved Ludwigia; 

 L. alternefolia, Alternate-leaved Ludwigia; L. 

 hirtella, Hairy Ludwigia; L. alta. Wing-stemmed 

 Ludwigia, and several Ludwigianthas and Isnar- 

 dias, kindred species of similar habit and character; 

 all fairly good oxygenators for aquarium and 

 aqua-terrarium culture. 



Ludwigia palustris (LAnn.) or Marsh Purslain, 

 Fig. 1 1 8, is a recumbent or floating aquatic, rooting 

 in the mud of ditches and swamps, having opposite 

 spatulate leaves, acute at the apex and narrowed 

 into a slender petiole or stem; with axillary 

 flowers having bractlets at the base of the calyx, 

 triangular lobes and reddish petals. The branching and erect stems are 

 of purplish-red color and the submerged leaves a golden-red and pale- 

 green, and the emersed leaves a lustrous dark-green, all having distinct 



FIG. 118. Marsh Purslain, 

 Lutiivigia palustris. Reduced one- 

 third. 



192 



