THE PHYLOGENY OF THE NEMOCERA, WITH NOTES ON THE LEG BRISTLES, HAIRS AND CERTAIN MOUTH GLANDS OF DIPTERA. 1 W. WESCHE, F.R.M.S. Professor Williston has published a paper 2 on the antennae of Diptera which is not only a remai kable analysis of these organs, but one showing an encyclopaedic knowledge. His deductions combined with his observations on other characters seem to me of great weight and importance, and may lead to a more exact classification of the order. On page 326 of the cited paper, in commenting on the number of antennal joints in the different families of Diptera, he says: ' We are at once struck with the predominance of five groups having a maximum normal number of sixteen, fifteen, ten, six and five. And I venture to suggest that these five groups repre-sent in the main five different divergent phyla of Diptera." These groups are: Group i. Families having from twelve to sixteen joints: Tipulidae, Cecidomyidse, Psychodidae, Mycetophilidae, Pachy-neurinae, Rhyphidae. Group 2.-Families with from six to fifteen joints: Dixidae, Culicidae, Blepharoceridae, Chironomidae. Group j. Families with from seven to ten joints: Scatopsinae, Simulidae, Xylophaginae, Stratiomyidae, Acanthomeridae, Taban-idae. Group 4. Families with from three to six joints : Nemistrinidae, Lonchopteridae, Phoridae, Cyclorrhapha. 1 The MS. of the present article was sent to me some time before his death by the late Mr. Wesche, with a request for comment and criticisms. In editing the paper, which Mr. Wesche had not quite completed, I have made no changes what-ever except verbal ones, and have omitted only a few immaterial parts. Most of his conclusions seem well taken, and it is to be regretted that the author could not have been spared to continue his researches along the fruitful lines that he had begun. S. W. WILLISTON. 2 BIOLOGICAL BULLETIN, XIII., p. 324, 1907. 250
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