402 



PASTURAGE AND 0\'ERSTOCKING. 



device (Fia'. 155). A smooth glass surface moistened with 

 thin honey is covered with a screen placed in a slanting posi- 

 tion and graduated. The bees which reach the farthest on 

 the glass may be selected for breeding, provided they are 

 equally proficient in other respects. 



^^^ 



Pig. 157. 



RED CLOVER. 



(From Vilmorin-Andrieux, Paris.) 



Another desirable attainment is red clover with a shorter 

 coi'olla. This will probably be secured only by hybridiza- 

 tion. 



702. The linden, or bass-wood {Tilia Americana, fig. 158)^ 



