1 88 



FLOWER-LAND. 



spurge, becomes, when it is dried, 

 our india rubber. 



I daresay you have often noticed 

 the " gum " upon the plum or cherry 

 trees, or the "resinous " substance 

 upon the firs (Fig. 167). These 

 are formed in the cells, vessels, and 

 )w *_ inter-cellular spaces of various parts 

 ing resin ducts. o f t h e plants in which they are 



produced ; as also the 



oil or scent which you 



find so pleasant when you 



bruise a myrtle leaf, or 



bend and squeeze the 



rind of an orange or 



lemon * (Fig. 168). 



You see how much there _. 



Fig. ib8. Oil cavity with drop of 

 is for you to enquire about volatile oil (0), from below the upper 



surface of a leaf of Dictamnus 

 and examine, not Only (foreign), magnified 320 times. 



concerning the way plants are made up, but also as to 

 the substances which they contain. 



But we must pass on to the way in which plants 

 live and grow. So I shall conclude our talks upon 

 the anatomy of plants by telling you about the 

 beautiful bloom which you often see upon our choicest 

 fruits. What is the "bloom," and what is it for? 



* Notice the leaves of the St. John's wort (Hypericum perforatuni), 

 which have these oil cavities ; they appear like transparent dots or spots. 



