THE DIPTEROUS GENUS DOLICHOPUS IN NORTH AMERICA. 3 



[fig. 207a, this article] * * * I observed in September the maneuvers of the male 

 in coiu-ting the female. He would place himself directly in front of her, at a distance 

 of about half an inch, with his face toward her. He would then rapidly vibrate his 

 wings, holding them horizontally at right angles to the body; and at the same time 

 would give these fore feet an up and down motion, raising them simultaneously to 

 the level of the head and bring them down with a slight force upon the ground, the 

 movement reciuring in a measured way in about half a second. This he would con- 

 tinue for about 10 seconds; then, rising on the wing, he would swiftly make a small 

 semicircle in the air and attempt to alight upon the female. In the large number of 

 cases that I observed, he was always unsuccessful, the female hastily moving away 



Fig. 1, — DOLICHOPUS bolsteri, new species. 



a few inches, when the male would usually alight before her and repeat the move- 

 ments. * * * I saw the same maneuver repeated hundreds of times. * * * 



In company with the species just mentioned occurred considerable numbers of 

 * * * crenatus 0. S. These were engaged in a similar occupation. The male of 

 this species has only plain tarsi, but differs from the female in having the antennal 

 joints longer, the first two with coarse black hair, and the arista of the third joint 

 heavily covered with a black pubescence [fig. 159a, this article]; the face is also longer, 

 the wings broader, and the cilia of the calypters, instead of being coarse and chiefly 

 black, are fine and white. The male hovers in the air before the female at a distance 

 of one or two inches, occasionally making a slight darting motion towards her. In this 

 position the peculiarities of his face and antennae are shown to the best advantage. 



In the Zoologisclier Anzeiger for April, 1889, Friedrich Dahl has 

 described the actions of Dolichopus plumipe-^ Scopoli, as he observed 



