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horns formed by the division of a single epidermal cell: 

 Sometimes one of the outer cells of a stem divides, in 

 the same manner as the epidermal cells and grows into 

 a stemless hair, but these hairs are of rare occurrence. 

 The cells composing the stem are, for the most part, 

 living and active, on applying salt-solution or glycerine, 

 the primordial schlauch rapidly contracts; the rays or 

 horns are thick-walled and show no plasmolyse although 

 they seldom contain air bubbles; where they join the 

 stem the wall between is seen to contain frequent pores. 

 A leaf, completely wilted, was placed with both surfaces 

 in water, the stem being carefully protected, in less than 

 half an hour it was fresh and stiff. 



Phlomis fruticosa L. is another example similar to 

 this in anatomical character. Less difference occurs in 

 the size of the various hairs, the stem varies in size and 

 length but there are fewer stemless hairs. This leaf 

 regained its turgescence also when placed with both 

 surfaces in water in less than an hour, when simply 

 brushed with water, in an hour and a half. As the stem 

 was smaller in diameter than the foregoing, it was easier 

 to experiment with in regard to the exact place where 

 the water drawn out by the salt solution passed through 

 the wall. The solution was applied to the uninjured leaf 

 surface, allowed to lie 20 minutes, sections rapidly made 

 and oil applied. Not only once or twice, but repeatedly, 

 the upper cells of the stem were found to be plasmolytic 

 while those lying between these and the epidermis had 

 lost no water. This proves conclusively that the water 

 passed through the outer wall of the hair cell, or what 

 is the same thing, that water could easily be absorbed 



