In 1955 Steve Taber extracted the oil soluable portion from
pollen and placed it on cellulose made from refined sawdust.  Bees
collected the sawdust "like mad" and ignored the pollen from which the
extract had come.
 
        The account of his work is found in the proceedings of the 1963
Apimondia Congress in Prague entitled "Why Bees Collect Pollen."
 
        Rolf Boch has also identified some attractant compounds from bee
trapped pollens.