Peas and Clover 151 
great force on a younger flower), the keel opens 
along its whole length, and the longer as well 
as the shorter stamens, together with the much 
elongated curved pistil, spring forth with violence. 
The flattened, spoon-like extremity of the pistil rests 
for a time on the back of the bee, and leaves on it 
the load of pollen with which it 
is charged. As soon as the bee 
flies away, the pistil instantly 
curls round,so that the stigmatic 
surface is now upturned, and 
occupies a position in which it 
would be rubbed against the abdomen of another bee 
visiting the same flower. Thus, when the pistil first 
escapes from the keel, the stigma is rubbed against 
the back of the bee, dusted with pollen from the longer 
stamens, either of the same or another flower; and 
afterwards against the lower surface of the bee, 
dusted with pollen from the shorter stamens, which 
is often shed a day or two before that from the 
longer stamens. By this mechanism cross-fertilisa- 
tion is rendered almost inevitable.” It will be noted 
that Broom is without a spine, and its leaves are of 
the three-foliolate character seen in the seedlings of 
Furze. Furze has no doubt been evolved from a 
Broom-like plant. 
In the Lucerne genus (Medicago) the flowers are 
honeyed, and therefore one of the stamens is free, to 
allow access to the honey. Each wing is united to 
the keel by a couple of processes, one pointing 
forwards and the other backwards, and locking into a 
depression in the keel. These points are most easily 
seen in the cultivated Lucerne, or Purple Medick 
Broom, 2nd condition 
