Bramble-bees and Others 



so much so that the edges of the disk rest 

 upon the ledge. No better result would be 

 obtained had they been cut out with the aid 

 of compasses. At times, again, the piece pro- 

 jects slightly beyond the mouth, so that, to 

 enter, it has to be pressed down and curved 

 cupwise. There is no variation in the dia- 

 meter of the first pieces placed in position, 

 those nearest to the honey. They are all of 

 the same size and thus form a flat cover which 

 does not encroach on the cell and will not 

 afterwards Interfere with the larva, as a con- 

 vex ceiling would. The subsequent disks, 

 when the pile is numerous, are a little larger; 

 they only fit the mouth by yielding to pressure 

 and becoming concave. The Bee seems to 

 make a point of this concavity, for it serves 

 as a mould to receive the convex bottom of 

 the next cell. 



When the row of cells is finished, the task 

 still remains of blocking up the entrance to 

 the gallery with a safety-stopper similar to 

 the earthen plug with which the Osmia closes 

 her reeds. The Bee then returns to the free 

 and easy use of the scissors which we noticed 

 at the beginning when she was fencing off the 

 back part of the Earth-worm's too-deep bur- 



250 



