BOTANY. 



so that the portion of the shoot between two 

 such adjacent rings, or above the last one, rep- 

 resents the growth in length of the shoot for one 

 year. At the close of the season's growth the 

 "bud" is formed. In the horse-chestnut the 

 terminal bud is broader than the diameter of the 

 shoot, and is ovate in form. 



15. We notice that there are a number of 

 scales which overlap each other somewhat as 

 shingles do on a roof, only they are turned in 

 the opposite direction. If we begin at the base 

 of the bud, we can see that the two lowest 

 scales are opposite each other, and that the two 

 next higher ones are also opposite each other, 

 and set at right angles to the position of the 

 lower pair. In the same manner successive 

 pairs of scales alternate, so that the third, fifth, 

 seventh, etc. , are exactly over the first, and the 

 fourth, sixth, etc. , are exactly over the second. 

 Aside from the fact that these brown scales fit 

 closely together over the bud, we notice that 

 they are covered with a sticky substance which 

 helps to keep out the surface water. Thus a 

 very complete armature is provided for the pro- 

 tection of the young leaves inside. 



16. Leaf scars. The number of leaves de- 

 veloped during one season's growth in length 

 of the shoot can be determined by counting the 

 broad whitish scars which are situated just 

 below each pair of lateral buds. Near the 

 margin of these scars in the horse-chestnut are 



^ seen prominent pits arranged in a row. These 



_ Two-year old twig ]j tt i e pits in the leaf scar are formed by the 



of horse chestnut. 



showing buds and breaking away of the fibro-vascular bundles 



leaf scars. (A twig 



with a terminal bud ( w hich run into the petiole of the leaf) as the 



should have been v 



selected for this fig- j ea f f a n s i n the autumn. 



ure.) 



