ZooL.— Vol. II.] WHEELER— DOLICHOPODIDjE. 17 



Four males and one female taken near Monterey, Calif., 

 July 13th to 22d, 1896. 



The extensive and peculiar distribution of the black on 

 the legs and antennae of this species, together with the gen- 

 tle upward curvature of the fourth vein, will readily distin- 

 guish it from all the other species of the genus. 



18. Pelastoneurus cyaneus, sp. nov. 



Plate I, Figs, 16-18. 



Male. Length 3.5-4.5 mm. ; length of wing 3-4 mm. Proboscis dull black. 



Palpi covered with white dust. Face rather narrow, covered with white 



dust which grows thmner on the upper portion, so that the metallic green 



ground-color is revealed. Antennae rather small ; first and second joints yellow 



with black upper surfaces; third joint rounded, black with a narrow yellow 



base; arista short, rapidly tapering and but slightly plumose. Front metallic 



green with violet reflections. Postocular cilia black. Thorax and scutellum 



bright metallic violet, the former somewhat more golden green anteriorly 



and dusted with yellow. Posthumeral depressions conspicuous with silvery 



white dust, passing into emerald green anteriorly. The deep black band on 



either side of the thoracic dorsum widens into three successive blotches, one 



mesial to the posthumeral depression, one at the root of the wing and another 



near the anterolateral insertion of the scutellum. There is also a small but 



distinct silvery white spot in front of the hindermost black blotch. Abdomen 



metallic violet, with black incisures and large patches of silvery white dust on 



the sides of the segments. Hypopygium two-thirds as long as the abdomen, 



with large, swollen base, black, with metallic green reflections and dusted 



with white, opaque except on the upper (morphologically ventral) portion, 



which is shining black. Lamellae very small, subtriangular, black, fringed 



with black cilia; inner appendages slender, black. Pleurae metallic blackish 



green, dusted with white. Coxas concolorous with the pleurae, all of them 



with distinct yellow tips, fore coxae with silvery white dust and prominent 



black hairs on their anterior surfaces. Legs yellow. Fore tarsi blackened 



from the tip of the first joint; second and third joints covered with dense, 



short white hairs on their plantar surfaces. Middle and hind tarsi blackened 



from the tip of the second joint; tip of the first tarsal joint, tip of the fore 



and middle tibiae and tip of hind femur blackened. Wings grayish hyaline, 



slightly darker towards the costal border, with black veins. Venation typical 



except that the angle on the fourth vein is not very prominent. Tegute and 



halteres yellow, the former with black cilia. 



Female. Length 4-5 mm. ; length of wing 4-5 mm. Palpi covered with 

 white dust. Face swollen below, covered with dull ochre-yellow dust, which 

 becomes gray along the orbit. Front metallic green or violet, with a dense 

 accumulation of ochre-yellow dust above the insertions of the antennae. 

 Thorax shining bronze, black anteriorly, metallic violet posteriorly. There 

 are three deep black connected blotches on either side as in the male; the 

 broad posthumeral depression is filled with pale ochreous or greenish white 



(2) 



Sept. 14, \i 



