Alfalfa in Kansas. 



199 



Crossing Alfalfa. 



The method thus far described is the method of selection. By this 

 means nothing new is originated. We have simply found out, and sorted 

 out superior alfalfa plants from the general lot. 



Suppose we now wish to put together, into a new plant, characters 

 existing only in different plants. To do this we must resort to crossing. 



alfalfa flower. 

 Fia. 173. Standard or upper petal of 



Let us now study the structure of an alfalfa flower. If we examine the 

 flower we notice that at the base there is an outside green hull with 

 pointed segments. This hull is called the calyx, and its five segments are 

 called the sepals. The purple flower portion protruding from the calyx 

 is the corolla, consisting of five petals, viz., the standard, the two wings, 

 and the two petals joined together, which form the keel. Removing the 

 petals, we find within a column-like structure of a whitish color. This 



