[Berliner Entomolog. Zeitschrift Bd. XXXT. 1887. Heft n.] 163 Studies on Tipulidae. Part. II. Review of the püblished genera of the Tipulidae brevipalpi, C R. Osten Sacken. Preface. In Publishing this seconcl instalment of my „Studies etc.", I re-peat what I said in the preface to the first: that unable to fulfil my original plan of bringing out a Genera of the Tipulidae I publish the material I had collected for its execution. As the classilication of the Tipulidae brevipalpi and the description of all their genera known at that time has been given in considerable detail in the fourth volume of the Monographs of North -American Diptera, the present paper is merely intended as a Supplement to it, bringing the subject up to date; hence the constant references to that volume i). Like the first part of these Studies, the present one is, in a great measure, composed from notes, taken by me in different collections. This mode of composition, besides being very laborious, involves considerable risks of error and confusion. If, instead of my notes, I had the specimens themselves before me, I miglit perhaps have obtained more satisfactory results and avoided some blunders (like that about Ctedonia). As it is, what I can offer, is often an exposition of my doubts and hesitations, much more thau of positive results. But even in this shape I liope that my work will spare some amount of labor to those wlio will come after me. To these successors I am free to give a piece of advice, as the result of more than 30 years experience with Tipulidae, and this is, not to introducc new genera prematurely: Large accessions of new forms, or of variations of already well-know forms must be expected from as yet unexplored, principally tropical regions ; but these acces-i) The fourth volume of the „Monographs" besides being often advertised iu the Catalogues of booksellers , may be found in most of the larger public libraries under the heading of: ,,Smithsonian Mis-cellancous Collections, Vol. VIII", I insist upon this detail, because the Monographs have often been missed in libraries for not being ca-talogued as a separate work. XXXI. Heft II. 11
BioStor
