-109- 
At Edgcrton P. fuse a and P. rugosa also predominated. P. hirticula 
was abundant there in 1935 » the year of the previous "A Brood" flight, 
but scarce in 1938. Figure 3 shows that, of the four predominant species, 
P. fusca was the most abundant on May 13, when the temperature was 5^ F. 
and on May 20, when the temperature was 58°, but had declined by June 2, 
when the temperature w£s also 58°. Apparently 58° is high enough to pro- 
duce a slow emergence of P. rugosa when the season is sufficiently 
advanced. 
Blue Mounds is near the north edge of the area in which P. hirticula 
is much more abundant than any other species. P. hirticula was predominant 
at Blue Mounds, but P, rugosa and P. fusca are also fairly abundant. 
Figure 3 shows P. hirticula to be most numerous in all the collections, 
made in that area. P. fusca \7as more common than ?. rugosa in the first 
collection, but diminished in numbers afterward as P. rugosa increased. 
