GLOSSARY xxiii 



Radicle, the root of the embryo. 



Receptacle, the axis of the flower, generally more or less thickened. 

 Rhizome, an underground stem, generally more or less thickened. 

 Rostellum (p. 401), the non-receptive third stigma of an Orchid flower. 



Samara, a winged fi-uit. 



Scape, a leafless stem bearing flowers. 



Sclerenchyma, hard tissue, for support (mechanical tissue). 



Sepals (p. 3), the leaves of the calyx. 



Septicidal dehiscence, of a capsule splitting along the septum which 



separates the constituent chambers. 

 Silicilla or silicule (p. 85), u. siliqua which is not longer than broad. 

 Silio[Ua, the fruit characteristic of Cruciferae, opening longitudinally by 



two valves which separate from a central septum. 

 Spike, like a raceme {q.v.), but with sessile flowers. 

 Stamens (p. 4), the parts of a flower which generally stand next the 



corolla, on the inner side. They usually consist of a stalk or iilament, 



and an anther, containing the pollen. 

 Staminode, a barren stamen, generally much reduced in size. 

 Stigma (p. 4), that portion of the pistil on which the pollen must be 



deposited in order to fertilise the flower. 

 Stipule, an appendage of the base of the leaf, generally borne in 



pairs. 

 Stoma, the month or aperture between two adjacent epidermal cells. 

 Style, the stalk of the stigma. 



Testa, the seod-coat. 



Tetramerous, with parts in fours. 



Transpiration, the giving off of water-vapour by green leaves. 



Trimorphous, of species in which there are three forms of flowers, 



differing in the relative position of the anthers and stigma. 

 Trioecious (p. HO), having hermaphrodite, male, and female flowers on 



distinct plants. 

 Tripinnate (p. 50), thrice pinnate (q.v.). 



Umbel, an inflorescence in which several stalked flowers spring from 

 one point ; the youngest flowers are nearest the centre. 



Viviparous (p. 442) when the seed is replaced by a green shoot, as in 

 several Arctic and Alpine grasses. 



