W. G. DIETZ 345 THE HEBES GROUP OF THE DIPTEROUS GENUS TIPULA LINNAEUS BY W. G. DIETZ, M.D. In his paper entitled, "Tipula fallax and Others,"^ Professor Doane tabulates eight species of Tipula. Five of these he describes as new, the other three — hebes, fallax and grata — had been de-scribed by Loew. These species form a natural group, charac-terized by the structure of the eighth abdominal sternite and of the hypopygium, and which may briefly' be described as follows (see plate XIII) : First — -The posterior margin of the eighth sternite is incised on each side, forming thus three lobes except in new-comeri, the lobes always more or less densely clothed and fringed with hair; Second — -Below the apical appendages the latero-inferior margin of the ninth stelriite has an oval, or approxi-mately circular emargination, filled with a whitish membrane which widens out beyond the posterior margin and forms an appendage, called bj' Professor Doane the lateral appendage and which must not be confounded with the apical append-ages described by Mr. Robert E. Snodgrass.-From the mar-gin of the appendage project processes — called arms by Pro-fessor Doane — generally two or three, called the upper or first, middle or second, and lower or third process, respectively'. In general it may be said that the upper process is always chitinou?;, the middle generall}' so and the lower (third, when present) mem-branous and pendulous. In form these processes vary greatly, and it is here that they furnish the most important characters for the separation of the otherwise very closely allied species of the group. The arrangement of the mesonotal vittae is so nearly uniform as to be almost characteristic of the group. The lateral stripes are described in the text as concolorous and margined with 1 Psyche, xviii, 160. -The Hypopygium of the Tipulidae. Trans. Am. Ent. Soc, xxx, 179 et seq. TR.\NS. AM. f:NT. SOC, XL.
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