CHLOROPHYLL CORPUSCLES 



of the stem or leaf. In many plants they appear 

 like disks, presenting in moderate light their flat or 

 broad sides to it ; but when the heat or light of the 

 rays become excessive they turn to it their narrow 

 edges only. The number of the chlorophyll corpus- 

 cles varies in the plasma of the cells from two or 

 three to upwards of many hundreds. In some of 

 the Algse they line the tubular cells so closely as to 

 appear like a continuous, unbroken coating. In 

 other varieties they form spiral bands; in others 

 stellate, discontinuous, or overlapping bodies. In 

 the leaves of the higher order of plants the upper 

 layer of the leaf, the so-called Pallisades, contain five 

 or six times the number of the green corpuscles that 

 the lower layer, the spongy Parenchyma, do. In the 

 former they lie so closely together that they appear to 

 constitute the entire substance of the cell, but close 

 examination, shows that they are only in the lining 

 substance of the cells, their interior not containing 

 even a single one, the plasmic cell sap, or sap juice, 

 alone filling the interior. 



In reference to the modus operandi of the Chlorophyll 

 corpuscles by which their wonderful work is accom- 

 plished, Kerner Von Marilaun remarks : " If, after 

 describing the form, arrangement and number of 

 these bodies we should ask by what means do they 

 accomplish the formation of organic matter in the 



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