37 
apical margin four anteriorly recurved hooks of an intermediate 
size, two on each side with a wide median interval. Each lateral 
pair on 4 and 5 are nearly as close-set as the anterior dorsal hooks; 
those on 6 and 7 are nearly as far apart as the median interval. 
The cocoon is of the usual color and “wall-pocket” form. 
S. meridionale Riley (Fig. 8).—This species, which is known 
as the turkey-gnat, is one of the most troublesome and wide-spread 
black-flies in the United States. It appears to be the predominant 
Pig. 8. The Turkey-gnat, Simu- 
liurn meridionale, front of head. 
X 35. (Drawn from dried speci¬ 
mens; structure of palpi not to be 
depended on.) 
element in the great spring outbreaks along our larger Illinois 
rivers—the Illinois, the Mississippi, and the Wabash. We have it 
from several points in the river bottoms and on the margins of 
the bluffs about Havana. Osborn says in his “Insects affecting 
Domestic Animals”* that “in this species the breeding grounds are 
limited to the smaller streams and branches, and the larvae are 
found attached to submerged dead leaves.” Adults are in our col¬ 
lections from Mt. Carmel, White county, on the Wabash; from 
Greene county, on the lower Illinois; and from Normal, McLean 
county. Still others were collected near a small creek at Aledo, in 
Mercer county, well up towards northern Illinois. All were taken 
between April 9 and May 13. The time of maximum abundance 
in central Illinois in two successive years was about April 25. 
The range of the species outside Illinois is very broad, includ¬ 
ing New Hampshire, Massachusetts, Virginia, Kentucky, Nebraska, 
Louisiana, Texas, and New Mexico. Notwithstanding its occa¬ 
sional occurrence far to the north, it is essentially a southern spe¬ 
cies, and it is most abundant to the southward in this state. 
*Bull. No. 5. N- Ser., Bureau of Ent., U. S. Dept. Agr. 
