OE, GLIMPSES BENEATH THE WATERS. 



plants proving of mutual value and support to each 

 other. The snails disposed of the decaying leaves, 

 which would have tainted the water and rendered it 

 unfit for the healthy existence of the plant, and the 

 plant in turn gave forth, under the rays of sunlight, 

 the supply of oxygen necessary to both fish and 

 snails. 



In January, 1852, Mr. Warrington, commenced 

 a series of similar experiments with sea-water; 

 Avhich were, at first, not so satisfactory, but in the 

 end proved as entirely successful. In the course of 

 his experiments, he found the red and brown Algce, 

 or sea-weed, less proper for the formation of oxygen 

 than the green. Of the latter class he procured 

 specimens of UnteromorpJia and Ulva latissima, 

 which he chiselled from the rocks about Broad- 

 stairs, along with the pieces of chalk or flint to 

 which they were attached ; and, when he placed them 

 in his own marine Aquarium, he put in along with 

 them, to represent the pond- snails in the fresh- 

 water tank, some of the common sea-snail, better 

 known as the Periwinkle {Littorina lUtorea). But 

 these proved, it appears, insufficient for the de- 

 struction of the mucous and gelatinous matter that 

 arose from the decay of the red sea-weeds, which, 

 however, I have no doubt may yet be cultivated with 



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