GLOSSARY 383 
Tracheae. The ducts or vessels of wood; chains of elongated 
cells the cross partitions between which have more or 
less completely disappeared. 
Tracheides. Short pitted or spirally thickened cells replac- 
ing tracheae as water channels in the wood of most gym- 
nosperms. 
Trailing. Slender-stemmed, prostrate on the ground. 
Transverse. Used sometimes in the sense of transversely 
- lengthened. 
Transversely joined leaf-scars. Those of a pair or whorl con- 
nected by a ridge or line running around the twig. 
Tree. A woody plant, usually of large size or with a single 
trunk when smaller. Contrasted with shrub, but not 
easily separated in definition, as sumach, witch hazel and 
many other plants show. 
Trichomes. The same as hairs. 
Trifoliolate. Of 3 leaflets, as applied to compound leaves. 
Truncate. Abruptly cut off (seed of hardy catalpa; petiole 
of fendlera; leaf-scar of sorbaria). 
Truncately. In a truncate manner. 
Trunk. The main stem or axis of a tree. 
Tuberculate. Warty. 
Tube. The lower tubular part of a gamophyllous calyx or 
corolla, etc. 
Twig-spine. A spine metamorphosed from a twig. 
Twigs. The finer or finest branches of a stem. 
Twiggy. Used in the sense of having many divergent twigs. 
Twinned-hairs. Two-armed appressed hairs (dogwood). 
Unarmed. Without either spines or prickles,—though the 
leaves may have pungent teeth or tip as in holly. 
Unifoliolate. Really compound, though of only one leafiet 
(leaf of barberry or orange). 
Uniform. Neither diaphragmed nor gritty, as here applied 
to pith. 
