DEVELOPMENT OF LEAVES AND STIPULES 61 



THE PLANE (PLATANUS) 



The leaf of the Plane originates in a ridge which 



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FIGS. 102, 103. LEAF DEVELOPMENT IN PLATANUS OCCIDENTALIS. 



The upper figure shows the growth of the first leaf-ridge (o 1 ) round the growing- 

 point, A. The ridge is not yet complete, being still open towards the front. 

 The outermost row of cells is the inner surface of the base of the protecting 

 leaf-stalk. 



The lower figure (transverse section) shows three leaf-ridges (oSo'.o 3 ) surrounding 

 the growing- point, A. The youngest ridge (o 1 ) is still incomplete. 



runs round the whole axis immediately below the grow- 

 ing-point. 



