64 FOUNDATIONS OF BOTANY 



How many leaves were there ? 

 Were they all of the same size ? 



(c) What has the mode of branching to do with the arrangement 

 of the leaves ? with the flower-bud scars ? 



(d) The dots on the leaf-scars mark the position of the bundles 

 of ducts and wood-cells which run from the wood of the branch 

 through the leaf -stalk up into the leaf. 



78. Twig of Beech. Sketch a vigorous young twig of beech (or 

 of hickory, magnolia, tulip tree) in its winter condition, noting par- 

 ticularly the respects in which it differs from the horse-chestnut. 

 Describe in writing any facts not shown in the sketch. Notice that 

 the buds are not opposite, nor is the next one above any given bud 

 found directly above it, but part way round the stem from the posi- 

 tion of the first one. Ascertain, by studying several twigs and 

 counting around, 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 

 provided for the study of this feature. 



79. Relation of Leaf -Arrangement to Branching. 1 This 

 difference, referred to in Sect. 78, depends on the fact that 

 the leaves of the horse-chestnut were arranged in pairs, on 

 opposite 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 



1 The teacher in the Eastern and Middle States 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 observe for himself, with a little guid- 

 ance from the teacher, most of the points which Miss Newell suggests. If the 

 supply of material is abundant, the twigs employed in the lessons above 

 described need not be used further, but if material is scanty, the study of buds 

 may at once be taken up. (See also Bailey's Lessons with Plants, Part I.) 



