110 THE BUILDING OF BEES. 



The above rules are not without exception, for unnoticed 

 circumstances may have some influence on the building of 

 combs; but we think that we have stated the main causes of 

 variation. 



Propolis. 



236. This substance, which is used by the bees to coat 

 the inside of the bee-hive, and make it water and air tight, 

 is obtained from the resinous buds and limbs of trees; the 

 different varieties of poplar yield a rich supply. When first 

 gathered, it is usually of a bright golden color, and so sticky 

 that the bees never store it in cells, but apr)lv it at once to 

 the purposes for which they procured it. If a bee is caught 

 while bringing in a load, it will be found to adhere very firmly 

 to her legs. 



Huber planted in Spring some branches of the wild pop- 

 lar, before the leaves were developed, and placed them in pots 

 near his Apiary ; the bees alighted on them, separated the folds 

 of the large buds with their forceps, extracted the varnish in 

 threads, and loaded with it first one thigh and then the other; 

 for they convey it like pollen, from one leg to the other. 

 We have seen them thus remove the warm propolis from old 

 bottom-boards standing in the sun. 



Propolis is frequently gathered from the alder, horse- 

 chestnut, birch, and willow; and as some think, from pines 

 and other trees of the fir kind. Bees will often enter varnish- 

 ing shops, attracted evidently by their smell; and in the 

 vicinity of IMatamoras, Mexico, where propolis seems to be 

 scarce, we saw them using green paint from window-blinds, 

 and pitch from the rigging of a vessel. Bevan mentions the 

 fact of their carrying off: a composition of wax and turpen- 

 tine from the trees to which it had been applied. Dr. Evans 

 says he has seen them collect the balsamic varnish which coats 

 the young blossom-buds of the hollyhock, and has known 

 them to rest at least ten minutes on the same bud, moulding 

 the balsam with their fore-feet, and transferring it to the 

 hinder legs, as described by Huber. 



