In August, 1879, I met with a small Dipterous fly, Drosophila ampelophila Loew, in considerable numbers, and as the subject is of interest to entomologists, I give the result of my observations. I have to thank Professor Hagen, of Cambridge, for the determination of the species and other information, and also Professor Lintner, of Albany, for a copy of his article in the “Country Gentleman” of 1st Jan'y, 1880, on this insect, and from which I have largely drawn.