In the course of an investigation of insects affecting cucurbits, begun in a preliminary way in the season of 1897, as a part of the official work of the Division of Entomology of the Department of Agriculture, it was found that we have in addition to the common squash bug, Anasa tristis, DeG., a second species sufficiently resembling it as to have readily escaped the notice of the average observer, but at the same time quite distinct in all its stages. This species is Anasa armigera, Say, and it was first observed on cucurbits by the writer July 12, near colonial Beach, Va., where it occured on cucumbers. Afterward it was taken by the writer and Mr. F. C. Pratt, of the Division of Entomology, who has assisted in field investigations and collections on different cucurbits, at Ballston, Va., Poolesville and Seat pleasant, Md., and on the Conduit Road and at Tenleytown, D. C. At the last mentioned place it occured in great abudance on a late crop of cucumbers and watermelons. As late as the 29th of September, all stages of the insect were found, including the egg. The present year the species was found to be nearly as abundant in some locaties as the common squash bug. Such was the case at Marshall Hall, Md., and in one locality in the District of columbia. It was also observed on squash at College Station and Kensington, Md., and on cucumber at Cabin John, Md.
THE "ACCESSORY CHROMOSOME" OF ANASA TRISTIS
