THE BEAN FAMILY. 271 



so distinct from other plants that it is raised to the rank of a genus. 

 And a single genus may be regarded as forming an order by itself 

 there are several such cases known. In the scheme given above, each 

 species is represented as having two varieties, each genus as having 

 two species, and the order as consisting of two genera. 



298. The Bean and Fea Family, so far as the native 

 British and the commonly cultivated foreign plants belonging 

 to it are concerned, can be readily recognised by the charac- 

 teristic structure of the flowers, especially the corolla. It is 

 therefore taken first in our study of the chief families of 

 Dicotyledons. All the commoner British wild plants in 

 which the flower has a corolla resembling that of the Broad 

 Bean (i.e. consisting of standard, wings, and keel) are de- 

 scribed in this chapter. 



Fig. 96. Yellow Vetchling (Lathyrus aphaca\ 



In studying all the available plants belonging to this 

 family, note carefully their resemblances and differences, as 

 a basis for a knowledge of the general principles upon which 

 the classification of plants is founded. 



The Bean Family is one of the largest, and also one of 

 the most useful, among flowering plants. The family as a 

 whole is characterised by the fruit being, with rare ex- 

 ceptions, a pod (legume), whence its name Leguminosae. 



