PSYCHE VOL. XIX. FEBRUARY, 1912. No. 1 NEW NORTH AMERICAN DIPTERA. By Charles W. Johnson, Boston Society of Natural History, Boston, Mass. In the genus Cylindrotoma there is considerable variation in the venation of both species and individuals. The three speci-mens of C. distinctissima Wiedemann received from Herr. M. P. Riedel show very little variation, the second posterior cell is of almost uniform length (Fig. 1). The figure shown by Prof. J. G. Needham of "C. distinctissima Meigen, after van der Wulp" (N. Y. State Museum, bull. 124, pi. 15, fig. 4, 1908) does not rep-resent the species. In C. americana O. S. the two specimens before me from Capens, Moosehead Lake, Maine, July 11, 1907, have the second posterior cell the same length as the third (Fig. 2). Regarding the venation of C. splendens Doane (Fig. 5 after Doane) he says: — "Submarginal cell either longer or shorter than the first posterior cell. In two of my specimens it is longer in one wing and shorter in the other." In C. jiinda Coq. the base of the sec-ond posterior cell is slightly before the base of the third. C. tar-salis sp. nov. (Fig. 4) has normally a venation similar to C. distinc-tissima, but there are many abnormalities. Among the fourteen specimens, four have the second posterior cell as long as the third in one or both wings; one has the vein m^ obsolete with only a slight indication of the vein at the margin; another specimen has a very abnormal venation, in one wing a small cell is present at the base of the submarginal and first posterior cells, extending from the marginal cell to and partly over the base of the discal cell; the junction of vein m^ is imperfect in both wings. In C. anomala sp. n. (Fig. 3) the first posterior cell is petiolate and the anterior cross-vein extends to the petiole.