ZooL.— Vol, II.] WHEELER— DOLICHOPODID^. 1 3 



12. Pelastoneurus occidentalis, sp. nov. 



Plate I, Fig. 20. 



Male. Length 3 mm.; length of wing 3 mm. Proboscis black. Palpi 

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

 thick white dust. Antennae black, mesial and lower surfaces of the first and 

 second joints yellow; third joint rounded, pubescent; arista short, rapidly 

 tapering, moderately plumose. Front metallic violet. Postoculur cilia snow 

 white. Thorax black, with green and cupreous reflections; lateral black 

 band faint and the accumulation of brilliant white dust in the prealar depres- 

 sion inconsiderable. Abdomen metallic bronze green with black incisures 

 and with a large blotch of white dust on the side of each segment. Hairs 

 covering the segments rather abundant, black. Sixth segment entirely cov- 

 ered with thick gray dust. Hypopygium slender, nearly as long as the 

 abdomen, black dusted with gray. Lamellae long and pointed, with ragged, 

 bristly edges. Pleurae metallic green overlaid with thick gray dust. Coxae 

 of the same color as the pleurae except at the extreme tips which are yellow. 

 Legs yellow, tarsi infuscated towards their tips. Wings grayish hyaline, 

 with the typical venation of the genus. Halteres and tegulae pale yellow, the 

 latter with black cilia. 



Female. Length 4 mm.; length of wing 3.5 mm. Basal portion of third 

 antennal joint yellow. Face with brownish dust towards its middle. Front 

 dull black, covered with brown dust. The silvery prealar depressions of the 

 thorax are larger and more conspicuous than in the male. 



Four males and one female taken at Pacific Grove, Calif., 

 July 9th to 22nd, 1896. 



The most striking character of this species is the structure 

 of the hypopygial lamelloe. 



13. Pelastoneurus floridanus, sp. nov. 



Plate II, Fig. 26. 



Male. Length 3.5-4 mm.; length of wing 3-3.5 mm. Palpi and face 

 thickly and uniformly covered with silvery white dust, the former rather 

 large, the latter of the usual breadth for a male. Antennae yellow, the 

 broadly rounded tip of the third joint blackened. Arista rather short, taper- 

 ing, plumose. Front metallic violet along the orbits, cupreous in the center. 

 Postocular cilia black above, white below. Thorax shining bronze black 

 anteriorly, becoming metallic violet posteriorly. On either side the dorsum 

 is deep velvety black as far as the insertion of the scutellum. There is a very 

 bright and sharply outlined spot of silvery white dust in the posthumeral 

 depression on either side. Prescutellar region and scutellum bronze black, 

 cupreous, or metallic blue-green in different specimens. Abdomen dark 

 cupreous, with black incisures and a large patch of white dust on the side 



