ARBANGEMENT OF THE BUDS 65 



Here the leaves are opposite, but there are com- 

 monly four pairs at each node (see 88 a), and 

 there are several rows of leaves up and down 

 the stem. Such leaves are whorled or verticUlate 

 (terms applied to opposite parts of more than one 

 pair) . 



66. In most of the other shoots which we have 

 seen, the buds are not opposite, but alternate. If 

 all our conclusions in respect to vernation are cor- 

 rect, however, it must follow that there is some 

 method of arrangement of the alternate buds, for 

 the enfolded leaves (in the axils of which buds 

 are to develop) have definite positions with refer- 

 ence to each other. The effort of the leaves to 

 expose themselves to sunlight may have exerted 

 some influence in bringing about a definite arrange- 

 ment of leaves, although it is doubtful if this has 

 been the sole, or even the chief, cause. 



67. Let the pupil secure a twig of elm, mul- 

 berry, basswood, a stalk of grass, or of Indian 

 corn. Fig. 64 is an elm twig. The bud 3 is 

 directly above 1, and 2 is half way between them. 

 If this arrangement is true of the other buds, each 

 bud must be 180 degrees from every other. The 

 buds are therefore 2-ranked, and they are as far 

 apart, in angular distance, as they can be placed. 

 The pupil will now want to examine young, branchy 

 growths of the elm, to see if the leafy sprays 



