THE OAK. 



115 



It is interesting to notice the shape of the bud and the method 

 of expansion of the leaf upon different trees. In the Oak bud the 

 two sides of the leaf are folded together at the main rib. The 

 leaves are arranged alternately on the twig in sets of live, that is to 

 say, the sixth leaf is in a straight line above the first on the stem, 

 the seventh above the second, and so on. A spiral line taken round 

 the stem would have to encircle five leaves before it would arrive 

 at one directly over the leaf it first started from. 



EXPANSION OF FLOWER AND LEAF BUDS. 



