872 WEED FLORA OF IOWA 



Viscid. Sticky, glutinous. 



Wavy. Margin forms wavy line bending inward and outward 

 in succession. 



"Wedge-shaped. See Cuneate. 



Whorl. An arrangement of organs in a circle around a stem. 



Wing. 1. Any thin or membranous expansion attached to or 

 bordering an organ. 2. The lateral petal of a papilionaceous 

 flower. 



Winter annual. See Annual. 



Xylem. Woody part of fibrovascular bundle containing larger 

 continuous air-containing vessels; the water-conducting tissue. 



