. Annals of the Entomological Society of America. Entomology. AN INTERESTING FEATURE IN THE VENATION OF HELICOPSYCHE, THE MOLANNIDAE, AND THE LEPTOCERIDAE. By Cornelius Bettex, Lake Forest College. The conclusions recorded in a recent paper by Prof. Martynov* regarding the venation of the Trichopterous genus HeHcopsyche lead me to anticipate here one of several somewhat revolutionary views on the venation of the Trichoptera to which I have come during the progress of work on a rather extended report on that order of insects. For the sake of comparison a figure is here given of the venation of
. Annals of the Entomological Society of America. Entomology. AN INTERESTING FEATURE IN THE VENATION OF HELICOPSYCHE, THE MOLANNIDAE, AND THE LEPTOCERIDAE. By Cornelius Bettex, Lake Forest College. The conclusions recorded in a recent paper by Prof. Martynov* regarding the venation of the Trichopterous genus HeHcopsyche lead me to anticipate here one of several somewhat revolutionary views on the venation of the Trichoptera to which I have come during the progress of work on a rather extended report on that order of insects. For the sake of comparison a figure is here given of the venation of the fore wing of Rhyacophila (Fig. 1), representing an extremely primitive t3^pe. The homologies indicated in this figure are so simple as to require no comment except as regards the branches of subcosta (Sc) and of cubitus and the anals. None of these is here considered and attention is directed only to radius which in this genus appears in absolutely primi- tive condition, that is, with Ri running free to the margin and with the radial sector (Rs) dichotomously branched. In very many Trichoptera there is a cross vein from R3 to R4 setting off what is called the discal cell. Near the base of cell R4 (the cell bounded by R4 and Ro) there is indicated a very small corneous point which is present in the vast majority of Tri- chopterous luA 'a Fig. 1. Venation of fore wing of Rhyacophila sp. Martynov reaches the conclusion that radius is also found in practically the typical condition in HeHcopsyche (Fig. 2), that is, that cell R4 in both fore and hind wings is not obliter- ated by the fusion of R4 and R5 as might at first sight appear to be the case. *Martynov, A. B. On two Collections of Trichoptera from Peru. Annuaire du Musee Zool. de I'Acad. Imperiale des Sci. de St. Petersburg. Vol. 17 (1912), 40 pp., Figs. 1-59. 65. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance o
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