Elements of biology; a practical Elements of biology; a practical text-book correlating botany, zoology, and human physiology elementsofbiolog00hunt Year: [c1907] BUDS AND STEMS 103 is to compare the structures we found in the bud with the markings that we find on the outside of a branch. Let us take for this work a winter branch of the horse- chestnut tree.^ Place some branches in water in a warm room so that we may have some opened buds to look at later. Laboratory Suggestions. — A twig in its winter condition shows the position of the buds very plainly. Notice that the ter- minal buds are
Elements of biology; a practical Elements of biology; a practical text-book correlating botany, zoology, and human physiology elementsofbiolog00hunt Year: [c1907] BUDS AND STEMS 103 is to compare the structures we found in the bud with the markings that we find on the outside of a branch. Let us take for this work a winter branch of the horse- chestnut tree.^ Place some branches in water in a warm room so that we may have some opened buds to look at later. Laboratory Suggestions. — A twig in its winter condition shows the position of the buds very plainly. Notice that the ter- minal buds are larger than those on the sides of the branch. As the twig grew last year the scales covering the outside of the bud dropped off and the young shoot developed from the opened bud. The scales which dropped off left marks upon the surface of the twig, which run completely around the twig at a given point, forming a little ring. These rings tell the age of the branch. Estimate the age of the one you hold. Was the growth always the same each year? How might you account for the different rate of growth in different years? Just above the lateral buds are marks, known as leaf traces, that show the points at which leaves were attached. A care- ful inspection of the leaf traces reveals certain tiny scars arranged more or less in the form of a horseshoe. These scars mark the former position of bundles of tubes which we have already studied in connection with roots. They are, in fact, continuations of the same fibrovascular bundles which pass from the root up through the stem and out into the leaves, where we see them as the veins which act as the support of the soft green tissues of the leaf. The most important use to the plant of the fibrovascular bundles is the conduction of fluids from the roots to the leaves and from the leaves to the stem and root. The position of the leaf traces on the branch give us a clew as to the appearance of the leafy tree. If we find the leaf traces opposit
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