THE OPENING OF THE BUDS, CONCLUnED 



61 



of the other, so that they may be said to be 

 astride. If we examine the common white wil- 

 low, however, we shall find that one leaf com- 

 pletely enfolds another. There are, then, two ele- 

 ments in this tucking away in the bud, — the par- 

 ticular manner in which each leaf is folded, and 

 the way in which one leaf lies upon another. All 

 these matters are among the most interesting 

 phenomena of spring time, and it has, therefore, 

 come about that this prsefoliation or packing away 

 of the leaves in the bud is called vernation (in- 

 directly from the Latin word for spring). In the 

 same way, the 

 arrangement of 

 the parts of the 

 flower in the bud, 

 — which follows 

 the same forms as 

 the leaves do, — 

 is known as aesti- 

 vation (indirectly 

 from the Latin 

 for summer) . ^^^ ^^ 



^ ,, ,, ,, Vernation of one of the cultivated ferns. 



63a. Both the meth- 

 od of folding and the 



arrangement of the parts is commonly represented by a diagrammatic 

 eross-section of the swelling buds. The great Linnteus defined the methods 

 of vernation (or "foliation") by the diagrams which are reproduced in 

 Fig. 62. The key is as follows: No. 1, convolute; 2, involute; 



