The Trees of Vermont 239 



Summer wood. The wood produced late in the growing season, character- 

 ized by smaller ducts and cells and thicker walls than the earlier growths 

 possess; the outer portion of each annual increment. 



Superposed. Placed above, as one bud above another at a node. 



Suture. A junction or line of dehiscence. 



Tangential. At right angles to the medullary rays. 



Tangentially. In a tangential manner. 



Tangential-section. A longitudinal-section of a body at right angles to any 

 one of its radii; any longitudinal-section of a tree trunk which does not 

 pass through the pith. Page 195, VIII, f. 



Terete. Circular in cross-section. 



Terminal. Situated at the end of a branch. 



Ternate. In threes. 



Tetrahedral. HaviAg, or made up of, four faces (triangles). 



Texture. The disposition, arrangement or character presented by the dif- 

 ferent elements in the structure of the wood. 



Thorn. A stiff, woody, sharp-pointed projection. 



Thyrse. A contracted or ovoid and usually compact panicle. 



Tissue. The texture or material built up by the union of cells of similar 

 origin and character. 



Tolerant. Capable of enduring more or less heavy shade. 



Tomentose. Densely pubescent with matted wool. 



Toothed. With teeth or short projections. 



Torus. The part of the axis of a flower which bears the floral organs. 



Trachea. A duct or vessel. Page 195, IX, b. 



Tracheid. A long, slender cell, with closed ends and its walls thickened after 

 the cell has attained its full size. Page 195, IX, a. 



Transition. Change as from spring wood to summer wood. 



Transverse. Said of a wood section made at right angles with the axis of the 

 stem; across the grain. 



Tree. Usually defined as a plant with a woody stem, unbranched at or near 

 the base, reaching a height of at least 15 feet. 



Trunk. The main stem of a tree. 



Turbinate. Top-shaped. 



Tylosis. A growth, frequently exhibiting repeated cell-division, intruding 

 within the cavity of a duct or vessel from the wall of a contiguous grow- 

 ing cell. 



Umbel. A simple inflorescence of flowers on pedicels which radiate from the 



same point. Page 9. 

 Umbellate. Arranged in umbels. 



Undulate. With a wavy margin or surface. Page 8. 

 Uniseriate. In one horizontal row or series. 

 Unisexual. Of one sex, either staminate or pistillate; not perfect. 



Veins. Threads of fibro-vascular tissue in a leaf, petal, or other flat organ. 

 Vessel. A duct or jointed tube which becomes continuous by the more or less 



complete absorption of the intervening cross-walls. Page 195, IX, b. 

 Villose or Villous. Covered with long, soft hairs. 

 Viscid. Glutinous; sticky. 



War-p. To become uneven in outline, as by shrinkage; to become twisted or 



distorted out of shape. 

 Whorl. An arrangement of leaves or branches in a circle round an axis. 

 Wing. Any membranous or thin expansion bordering or surrounding an 



organ. 

 Wood. The hard part of a stem lying between the pith and the bark. 

 Wood elements. The cells or units making up the wood. 

 Wood fibers. Long, slender cells with thick walls and narrow cavities, which 



impart strength and toughness to the wood and bark. Page 195, IX, d. 

 Wood parenchymal. A several-celled fiber in which the end cells have pointed 



extremities while the intermediate cells have square ends. Page 195, 



IX, e. 

 Woolly. Covered with long and matted or tangled hairs. 



