Miller. — The Diptera Fauna of New Zealand. 185 



Genus Berismyia (iiglio-Tos. 



I have placed the following species, Exaireta alpina of Hutton, in this 

 genus on account of the position of the antennae below the middle line of 

 head and the presence of only three posterior veins in the wing. I have no 

 specimens of this species at my disposal beyond Hut ton's type species, 

 which is a female. 



B. alpina. 



Exaireta alpina Hutton, Trans N.Z. Inst., vol. 33, p. 5 (1901). 



?. A moderately large fly with bluish-green thorax and the abdomen 

 dark tawny, the sides of which and the posterior margin of each segment 

 dark green ; legs tawny and wings yellowish. At first sight this species 

 resembles in colour the female of A. opposita, but its much larger size and 

 margined abdomen, as well as the position of the antennae and number of 

 posterior- veins, at once place it as a distinct species. 



Eyes dichoptic, bare, occupying side of head in profile, a faint depression 

 a little above the antennae. Ocellar triangle and front blue-black and 

 shiny, the former more or less prominent and the latter with a patch of 

 silvery-grey tomentum above the antennae, which are elongate, being 

 longer than width of head, and situated below the middle line (fig. 11) ; 

 black in colour but for base and underside of 1st segment of the 3rd joint, 

 which is dark tawny ; 1st and 2nd joints bristly, the latter half as long 

 as the former ; 3rd joint composed of 8 segments, densely pubescent, and 

 terminating in several short and delicate hairs. 



Face shorter than front and strongly receding, covered by a silvery- 

 white tomentum (black in certain lights), along which is a dark medio- 

 longitudinal and narrow stripe Proboscis pale tawny palpi large and 

 projecting in front of proboscis ; penultimate jo ; nt elongate and narrow, 

 longer than the ultimate, and pale tawny with delicate hairs ; ultimate 

 joint fusiform, about two-thirds length of preceding, tawny at base and 

 on inner side, otherwise black. Occiput shiny black, more or less rounded, 

 with some scattered silver} 7 tomentum above but hairy below, and produced 

 backward at the oral margin. 



Thorax brilliant bluish-green, especially the pleurae, the sterno-pleurae 

 a darker green ; the dorsum with a scattered greyish tomentum. the pleurae 

 with silvery hairs. Humeral and post-alar calli dark tawny, the latter 

 golden in certain lights. Scutellum brilliant bluish-green margined with 

 tawny, the 4 spines short and dark tawny. 



Wings tinged with yellow r . deeper at the base and in costal and marginal 

 cells; veins yellow ; costal cell broadened slightly ; 1st submarginal cell proxi- 

 mally obtuse, the 1st section of 3rd vein not quite as long as anterior cross- 

 vein, which is slightly oblique anteriorly (fig- 12) ; 3rd vein slightly sinuated, 

 the anterior branch arising at right angles from the middle and strongly 

 bent to the costa ; only 3 posterior veins, there being no sign of a 4th ; 

 vein between discal and 4th poster' or cells not quite twice length of anterior 

 cross-vein. Distance from the margin of the confluence of the 5th and 

 6th veins not twice the length of anterior cross-vein. Anal angle strongly 

 rounded. Halteres yellow. 



Legs tawny, the femora and tibiae stout, the posterior femora thickened ; 

 anterior tarsi fuscous, especially the protarsi. 



Abdomen with 7 visible segments about as wide as thorax, oval or 

 almost rectangular excluding the 6th and 7th segments (fig. 13). The whole 

 tawny, but segments 1 to 5 bordered along the sides by deep shiny-green 

 which is continued across the middle of the 1st segment ; the 2nd to 5th 



