624 



BOTANY 



PART II 



Abimdautly represented in the temperate zones ; fewer in the tropics. 



The component parts of a papilionaceous flower ai'e seen separately in Fig. 642. 

 The p)osterior petal, which overlajis the others in the bud, is termed the standard 

 (vexillum). The two adjoining, lateral petals are the wings (alae), and the two 

 lowest petals, usually coherent by their lower margins, together form the keel 

 (carina). The upper ends of the stamens are usually free and curve upwards, as 

 does also the style bearing the stigma. 



f-<\- 



Fig. GiC.—Cytisus Lahurnvm (J iiat. size). Poitioxovs. 



Important Sub-Families and Genera. — The (1) Sopltoreae a.i\d (2) Podalyricac 

 approach the Caesaljiiniaceae in having the stamens more or less free. The former 

 is characterised by pinnate leaves, the latter by simple or palmate leaves. The 

 genus Myroxylon, belonging to the Sophoreae, is of importance on account of the 

 balsam obtained from species belonging to it. Myroxylon Pereirae is a tree of 

 moderate height with alternate, imparipinnate leaves (Fig. 643). The flowers are 

 borne in the terminal racemes and have a large vexillum, the other petals remaining 

 narrow and incoii.sincuous. Tlie stamens are only coherent at the base, and bear 



