182 Transactions. 



colour is bright yellow margined with black-bronze, except the 2 apical 

 segments which are coloured below as above. 



The <$ is smaller than $. Thorax black-bluish-green ; scutellum bright 

 bluish-green, the spines short and tawny. Wings with no clear spot in 2nd 

 posterior cell ; space in the 3rd and 4th posterior cells smaller ; 3rd posterior 

 vein in one specimen not reaching this space but in another entering it — 

 that is, the 3rd posterior vein of former specimen not reaching half-way to 

 the margin and not more than half-way in the wing of the latter. 



Abdomen long and linear, slightly restricted along the middle sides and 

 not quite as broad as thorax ; 1st segment without a tawny spot ; spot of 

 2nd smaller than that of $ and with a faintly darker central stripe ; the 

 3rd segment with a clear tawny spot on the anterior margin, and the 4th 

 with a similar but smaller spot. 



The ? and smaller S were bred by Mr. Philpott from pupae found under 

 the bark of a dead ribbonwood-tree at AVallacetown, while a larger <J was 

 captured by him on a tree-trunk at night on the West Plains. 



Another <$ captured by him in Otago measures only 7 mm., and wing 

 5 mm. The tawny spots of the abdomen are here indistinct, only to be 

 faintly seen in certain lights, and the wings are not so deeply clouded with 

 brown ; in this case the 3rd posterior vein barely reaches half-way to the 

 margin. 



o. Length, 8-9 mm. ; wing, 6-25-6-75 mm. 



$. Length, 8 mm ; wing, 7 mm. 



Habitat.- — West Plains (Otago), February ; Wallacetown, October. 



Genus Actina Meigen. 



This genus, as has been said, differs from Exaireta in the eyes being 

 pubescent, but on reviewing the wings we find further differences. In 

 Actina the costal cell is distinctly widened by a curve of the costa : this 

 is characteristic of six other new forms obtained after the following were 

 described, but which will form part of a future " contribution." The costal 

 cell is not widened in Exaireta. Again, the 3rd longitudinal vein is not 

 so strongly sinuated in Actina as in Exaireta. 



The two species mentioned below may be distinguished by the following 

 table : — 



(a.) First submarginal cell proximally obtuse ; abdomen tawny, 



with blackish-brown bands widening laterally . . . . opposite,. 



(b.) First submarginal cell j^roximally acute ; abdomen brownish- 

 black, 3rd to 5th segments with anterior tawny band .. simmondsii n. sp. 



A. opposita Walker. 



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

 Actina opposita Walker, Cat. Dipt. B.M., pt. 5, Supp., p. 13 (1854) ; 

 Hutton, Cat. Dipt. N.Z., p. 35. 



<$. A medium-sized fly with brilliant green thorax and tawny, banded 

 abdomen. 



Eyes with delicate scattered and yellow hairs, cupreous with no trans- 

 verse markings, closely approximated below middle line of front and occupy- 

 ing side of head in profile. Ocellar triangle Prussian blue, more or less 

 prominent, situated well in front of the posterior eye-corners — that is, as if 

 upon the front — the eye-corners at the vertex being well behind the triangle, 

 which bears some long hairs, apparently not arranged in series ; posterior 

 to the triangle the vertex is rounded, carrying long hairs, and of a brilliant 

 greenish-blue, this colour extending across the occiput to the foramen as an 



