40 



ELEMENTS OF BOTANY. 



any given bud found directly above it, but part way round the stem 

 from tlie position of the first one. Ascertain, by studying several twigs, 

 which bud is above the first and how many turns round the stem are 

 made in passing from the first to the one directly above it. 



Observe with especial care the difference between the beech and the 

 horse-chestnut in mode of branching, as shown in a large branch pro- 

 vided for the study of this feature. 



60. Relation of Leaf- 

 Arrangement to Branching?- 



— This difference depends 

 on the fact that the leaves 

 of the horse-chestnut were 

 arranged in pairs, on oppo- 

 site sides of the stem, while 

 those of the beech were 

 not in pairs. Since the 

 buds are found at the upper 

 edges of the leaf-scars, and 

 since most of the buds of 

 the horse-chestnut and the 

 beech are leaf -buds and 

 destined to form branches, 

 the mode of branching and 

 ultimately the form of the 

 tree must depend largely 

 on the arrangement of 

 leaves along the stem. 



61. Opposite Branching. 



— In trees the leaves and 

 buds of which are oppo- 

 site, the tendency will be to form twigs in two rows about at 

 right angles to each other along the sides of the branch, as 

 shown in Fig. 24. 



" The teacher will do well to make constant use, in the study of branches and 

 buds, of Miss Newell's Outlines of Lessons in Botany, Part I. The student can 

 make out for himself, with a little guidance from the teacher, most of the points 



Fio. 24. — Opposite Branching in a very 

 Young Sapling of Ash. 



