Attributes / relations provided by
♦ ¹Robertson, C. Flowers and insects lists of visitors of four hundred and fifty three flowers. 1929. The Science Press Printing Company Lancaster, PA.
♦ ²Clements, R. E., and F. L. Long. 1923, Experimental pollination. An outline of the ecology of flowers and insects. Washington, D.C., USA, Carnegie Institute of Washington.