21 



PLANT STUDIES 



one. Poi-haps the most coinpleto fitting together of leaves 

 is found in certain ivies, where a reguhir layer of angular 

 interlocking leaves is formed, the leaves fittiug together like 



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flu. IS. A plant {Ptlliijiihi) with droopiiic stems, slmwing liow the leaves are all 

 bruilght til the lighted side tiiid fitted together. 



tlie pieces of a mosaic. In fact such an arrangement is 

 known as llie mosaic nrnivgemcnt, and involves sucli ;in 

 amount of twisting, displacement, elongation of petioles, 



