GLOSSARY OF BOTANICAL TERMS 321 



Tuber, a short, thick, underground stem, stored with food 



material. 

 Turgid, distended with sap. 

 Umbel, an inflorescence in which the flowers are stalked, the 



stalks all radiating from a common point on the axis 



(p. 42). 

 Unisexual, applied to flowers which contain either male or 



female organs, but not both (p. 39). 

 Variation, a departure from type (p. 47). 

 Versatile, appUed to anthers which are balanced on the 



filament, and so swing freely. 

 Viviparous, germinating while attached to the parent plant 



(p. 157). 

 Water-stomata, special pores on the leaves of some plants 



which exude water (p. 76). 

 Whorled, applied to foliar and floral leaves, which are arranged 



in a circle, at one level on the axis. 

 Wing, a prolongation of a seed or fruit ; the lateral petal of a 



Leguminous flower. 

 Zygomorphic, applied to flowers, which are not divisible into 



two similar halves in more than one plane of symmetry. 



