CHAPTER I 

 TYPE I 



THE WALLFLOWER (Cheiranthus Clieiri, L. 1 ) 

 I. EXTERNAL CHARACTERS 



A. VEGETATIVE ORGANS 



a. The Shoot 



THE Wallflower, a native of Southern and Central 

 Europe, is occasionally found naturalised in England, 

 and derives its name from growing commonly on old 

 walls. It is a perennial that is to say, it lives for a 

 number ^ years. It does not die down in winter, nor 

 does it lose its leaves in autumn. The leaves, however, 

 gradually drop off from the older parts of the stem. 



The stem is erect and branched (see Fig. 1), and 

 its lower part is covered by scales of pale brown bark. 

 This part is hard and woody. The upper portions, 

 both of the main stem and branches, are softer and 

 coloured green, and are rather hairy. The surface of 

 the stem is ridged lengthways, the ridges being more 

 conspicuous on the younger parts. The ridges are 



1 The letter L is the initial of the author (Linneus) from whom the 

 plant received its present name. 



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