No CrossRef data available.
Published online by Cambridge University Press: 31 May 2012
Dr. Williston, in his painstaking work on the Syrphidœ says: “There are no generic and specific limitations in nature”, and illustrates the statement by the present knowledge of the family with which his synopsis deals. And what Dr. Williston brings forward is a mere quota of the mass of evidence brought out by natrualists generally, and entomologists dealing with the different order of insects.