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NOTES FROM THE BOTANIC GARDENS, SYDNEY. 



PARTHENOaENKSIS IX AQUATIC PHANEROGAMS. 



By a. H. S. Lucas, M.A., B.Sc. 



Elatine triandra Schrank [ELATiNACEiE]. 



Plants of Elatine were brought under my notice by Mr. J 

 Bi'ooks, who has charge of the freshwater aquaria at the Botanic 

 Gardens, Sydney, in February last. The plants were growing 

 submerged in a glass tank. They had grown vigorously for some 

 months, with roots fixed in the soil at the bottom of the tank. 

 Now, fragments were being detached freely, with rootlets grow- 

 ing out into the water, Mr. Brooks wanted to know — " Whv 

 are the plants breaking up in this way 1" 



Capsules in various stages of development were grow ing on 

 the plants, but no flowers or flower-buds could be discovered. 

 There were no signs of calyx- lobes, corolla, stamens, or even 

 bracts. A few of these capsules contained apparently fully de- 

 veloped, brown seeds presenting the characteristic sculpturing. 



Thinking that by modifying the conditions we might be able 

 to induce normal flowering, I asked Mr. Brooks to plant some in 

 earth in a flower-pot surrounded by water, and to expose these 

 gradually to full sunlight. 



A few days later, I discovered the plant growing in the Lily- 

 Pond of the Centennial Park, Sydney. Large, floating frag- 

 ments, up to 9 inches in length, with abundant roots, bore fruits 

 similar to those formed in the tank. At one spot, the floor of 

 the pond was dry, owing to the prolonged drought. Here the 

 plant was growing on firm mud. The leaves were very much 

 shorter, and the plant altogether smaller, than in the submerged 

 form; but it bore numerous, small flowers, with 3, broad, green 

 sepals; 3, spreading, red pistils; and 3 stamens I brought 

 some home, with the surrounding mud, and planted them in an 

 ordinary flower-pot. I did not place the pot in water, but kept 



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