May, 1915.] 
Hemiptera-Heteroptera of Ohio. 
503 
Family Gerrid^e. 
Gerris canaliculatus Say. 
One macropterous specimen, taken by the junior writer, 
October 15, 1913, on the Olentangy River (Ohio State University 
Farm.) 
Gerris conformis Uhler. 
One specimen, taken at Ironton, Lawrence Co., by Mr. R. 
C. Osbum; numerous specimens, collected by the junior writer 
at Berea, Olmsted Falls, and Columbus. This is a lacustrine as 
well as a fluviatile species. In the localities cited, several nymphs 
and adults were taken at various times during the past summer 
on ponds, small lakes, and streams. During the winter, they 
hibernate as adults and begin to copulate in early spring. The 
ova are deposited on material just beneath the surface of the water. 
In an aquarium, they were laid on floating cork just beneath the 
surface film and fastened with a viscous substance which is water¬ 
proof. These eggs began hatching in eleven days and the first 
adults appeared thirty-four days later, several requiring a few 
days longer to complete their metamorphosis. There are proba¬ 
bly several generations during the summer, as nymphs and adults 
were taken on these same bodies of water during the latter part 
of the season. All specimens reared and collected were macrop¬ 
terous. 
Limnogonus hesione Kirkaldy. 
This tropical species is a noteworthy addition to our fauna. 
It has been recorded from Florida and Darien, Panama by Kirk¬ 
aldy (Entomologist, 1902, p. 137). 
One macropterous cf, taken during the past summer at Gabon, 
Crawford Co., by Mr. G. Iv. Rule; immense numbers of apterous 
cf and $ , collected by the junior writer at Buckeye Lake, and at 
Minerva Park north of Columbus during September and October 
1913, also at the latter locality and at the Ohio State Fair Ground 
in Columbus during September and October 1914. At these various 
times, numerous specimens were found copulating. Last October, 
several cf and $ were placed in an aquarium; in a few days eggs 
were deposited on floating cork just beneath the surface of the 
water. The males died a few days after coition, and the females 
a few days after the ova were deposited. Many of the individuals 
remained almost constantly in coitn for several days. As the 
ova and no adults could be found in early spring, the winter is 
probably spent entirely in the egg stage, while, later on and during 
the latter part of the summer, immense numbers were found on 
these same bodies of water. The eggs are slightly enlarged at one 
end and about three times as long as wide. They vary in length 
from one to one and one-third of a millimeter, and are of a dirty 
greenish-yellow color which becomes somewhat darker with age. 
