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 leaflet 

 (leaf of barberry or orange). 



Uniform. Neither diaphragmed nor gritty, as here applied 

 to pith. 



