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second kind of cell. These cells are large, without color, dead, 

 and perfectly empty. It is to the presence of these large, color- 

 less cells and to their remarkable structure, which I shall describe 

 next, that the sphagnum owes its wonderful power to take up 

 liquids. 



Now, to a certain extent, the cells of any moss leaf are able to 

 absorb liquids. But the ability of the ordinary green cells in 

 this respect is insignificant when compared with that of the large, 

 colorless cells of the sphagnum leaf. These, because of their 

 capacity for absorption, may well be referred to as the absorbing 

 cells. There are two features in these cells which especially 

 adapt them to the function of absorption. First, the wall of 

 each and every one of the absorbing cells is punctured toward 

 the outside by several minute holes or pores. It is through these 

 pores that liquids are sucked into the cells. Each cell, acting 

 independently, sucks in whatever liquid it comes in contact with 

 until it is full. A sphagnum plant with its hundreds of leaves, 

 each leaf containing hundreds of these tiny absorbing cells, 

 represents a highly efficient absorbing system. And this absorp- 

 tive ability is not confined to plants that are fresh. A dry, dead 

 leaf is just as efficient, when it comes to taking up liquids, as a 

 fresh one. This is due to the second structural peculiarity of the 

 absorbing cells. For inside of each one of these cells there is a 

 spiral, spring-like coil of thickening (or commonly a series of 

 hoop-like ribs of thickening) which presses outward, as it were, 

 against the walls of the cell and serves to keep it from collapsing. 

 Even after a leaf has become completely dried out, this "frame- 

 work" serves to keep the cell cavity open. 



Incidentally, while it is the leaves which are most efficient in 

 the absorption of liquids, in some varieties of sphagnum both the 

 stem and branches are enveloped by one or more layers of ab- 

 sorbing cells, essentially similar to those found in the leaves. 



It now becomes perfectly clear why it is that sphagnum is so 

 much superior to cotton as an absorbent. In cotton liquids, for 

 the most part, are merely held within a tangle of threads. In 

 the sphagnum we find a highly specialized absorbing system, 

 made up primarily of a vast series of absorbing cells, but supple- 



