. Monographs of the Diptera of North America [microform]. Diptera; Insects; Diptères; Insectes. â¢â | â «*f. .1 Ui 62 DIPTERA OP NORTH AMERICA. [part hi. that of S. vau so closely that I have no hesitation in placing it in the same genus. There are two other North American species which I take to be undoscribod, and which also belong to Stictocephala. As their wings are not pictured like those of the two preceding spe- cies, but simply banded, the difference between them seems, at first glance, to be greater than it really is. A close examination does not disclose any plastic difference whic
. Monographs of the Diptera of North America [microform]. Diptera; Insects; Diptères; Insectes. â¢â | â «*f. .1 Ui 62 DIPTERA OP NORTH AMERICA. [part hi. that of S. vau so closely that I have no hesitation in placing it in the same genus. There are two other North American species which I take to be undoscribod, and which also belong to Stictocephala. As their wings are not pictured like those of the two preceding spe- cies, but simply banded, the difference between them seems, at first glance, to be greater than it really is. A close examination does not disclose any plastic difference which would justify their generic separation from Stictocephala. I will describe them as Stictocephala cribrum and cribellum. The North American species described by Macquart as Platy- stoma annidipes shows, in the detail of its structure, an almost complete agreement with the species of Stictocephala, but differs so much in the outline of the wings and still more in the vena- tion, that it cannot be placed in that genus. The difference in the outline of the wings consists in the fact that the posterior margin is more convex, and hence, the wings are broader ; the difference in the venation appears in the posterior angle of the anal cell being drawn out in a very long lobe, and in the position of the posterior crossvein, the anterior end of which is much nearer to the apex of the wMng than the posterior end. As this species does not find a convenient place in any of the existing genera, I am compelled to establish a new one for it, which I call Callopistria. This would close the series of the few genera of Pterocallinci, hitherto sufficiently defined, if we had not to advert to the genus PsAiROPTERA Wahlb., occurring in northern and central Europe, as well as in northern Asia, a genus for which it is not easy to find an appropriate place in the system. The species of this genus resemble the Ulidina in their general appearance, and I would not have hesitated to place them in
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