HOW PLANTS LIVE AND WORK. 321 



centre of the flower, are unique. The delicate contours of the 

 petals rival in beauty the curves of a Greek urn, while the subtle 

 perfume of the flower in its turn appeals to another sense. We 

 feel, in short, that we have here something which is in its way 

 absolutely perfect, and we can understand why Heine, with all 

 his poet's imaginativeness, could find nothing to express admira- 

 tion and reverence better than ''^ Dii bist wie eine Blutne.''^ When 

 we remember, too, that the plant is as instinct with life as we 

 ourselves are, that it has to struggle for its existence as keenly as, 

 if less noisily than, we have, our imagination is further kindled. 

 Then, again, why have some Primroses long pistils and others 

 short ones ? Why are there Primroses and Cowslips (for it is 

 evident to the most casual observer that they are related) ? Why 

 do we so often find associated with Primroses a certain butterfly 

 whose colours exactly match those of the flower ? It is to answer 

 these and allied questions, in language free from tedious technical- 

 ities, in language " to be understanded of the people," that this 

 article is written. 



Get, then, this idea firmly fixed in your minds : plants are 

 alive. This fact, whicli you, of course, all knew before, may 

 acquire a new significance after a time. Now go out and buy, 

 beg, borrow, or otherwise obtain possession of a bunch of Wall- 

 flowers. 



Take one of these and examine it carefully and delicately. 

 First, notice the stem. It is green and soft nearest the flowers ; 

 further down it becomes brown and harder. It will be seen that 

 there are five ribs running down the stem. On these ribs the 

 lance-head-shaped leaves are inserted. Fix on any one leaf, and 

 the rib from which it springs. The next leaf springs from the 

 next rib, the third leaf from the third rib, and so on. We thus 

 find that the leaves are inserted spirally on the stem, and that 

 every fifth leaf is opposite the same rib. By turning a leaf uj) it 

 will be seen that its " mid-rib " (the principal " vein ") is continu- 

 ous with the rib on the stem. The mid-rib of the leaf divides 

 and subdivides until the whole blade is supported by a delicate 

 meshwork of so-called veins. The ribs on the stem and the 

 veins of the leaves contain an enormous number of little i)ipes, 

 by means of which every leaf receives a very efficient water-supply. 



