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Randolph : Influence of moisture upon ivy 



Figure i. Traced from a photograph of ivy stem grown in a greenhouse in air 

 slightly moist, showing the part of the stem that was under water. The lowest group 

 of holdfast-roots [kr) had grown together, forming a felt-like mat whose distal surface, 

 which had adhered to a wall, is turned toward the observer. From this distal side of 

 the mat of holdfast-roots absorptive roots (Ara) have arisen. A group of absorptive 

 roots springing from the stem (sa) slightly above has been turned aside in order to 

 leave the view of the holdfast-roots and their outgrowths unobstructed. 



