Fluke—Syrphidae of Wisconsin. 
231 
37. P. quadratus Say. Numerous specimens from Dane, Yernon, 
St. Croix, Pierce, Buffalo, Barron, Monroe, Jackson, Mil¬ 
waukee, Washington, and Bacine Counties. May to Octo¬ 
ber. Figure 30. Very common in the swamps. 
38. P. scambus Staeger. Two males from Vilas County. I be¬ 
lieve chaetopodus Will, is synonymous with scambus 
Staeg. 
39. P. species? Sauk County, July 29, 1918. One male among 
the reeds in Wisconsin River bottoms. I am unable to 
place this specimen with any described species, but until 
more material can be secured I prefer not to describe it 
as new, especially in this difficult genus. Length 9 mm. 
Front tibiae dilated very little, the outer angle below 
sharp and very little produced downward; front femora 
without a peculiar white hair at the base, with only a few 
weak black hairs and a small amount of light-colored pile 
intermixed. Figures 32, 33. 
Melanostoma Schiner 
1. Darker species, abdominal bands distinctly metallic, not red¬ 
dish yellow, pollen of face somewhat striate on the 
sides .. obscurum 
More yellowish species; abdomen of male with three pairs of 
quadrate yellow spots, female with four pairs of triangular 
or drop-like spots. 2 
2. Larger species; yellow of fifth segment entire, not interrupted, 
all the spots larger . angustatum 
Smaller species; yellow of fifth segment separated into spots, 
abdominal spots much smaller. mellinum 
40. M. obscurum Say. Manitowoc, Vilas, Juneau, Milwaukee, 
Washington, Jefferson, and Dane Counties. Common in 
early spring. Figure 34. 
41. M. mellinum Linn. Specimens from Dane, Mnnitowoc, St. 
Croix, Pierce, Buffalo, Monroe, Milwaukee, Washington, 
Douglas, Burnett, and Polk Counties. Early spring to 
late fall. Figure 36. 
42. M. angustatum Will. Numerous specimens, Madison, Dane 
County. Late summer and fall. Figure 35. A common 
species in the marsh. 
