HUNGERFORD: AQUATIC HEMIPTERA. 1 
Hibernation. De Geer, 1778, said of Gerris lacustris “. qu’il 
la gange pour se garantir contre le froid.” Our large G. remigis winters 
as an adult hidden under some brush, logs or other shelter about the 
water. 
Mating. De Geer also described the mating of Gerris. It begins in 
early spring and continues through the season. 
Oviposition Dufour described the eggs of Gerris and their deposition. 
They are laid on supports projecting from the water, and upon floating 
objects as a rule beneath the water line. They are fastened by means of 
water-proof glue. 
Incubation period. The writer finds it to be about two weeks for this 
species. 
Hatching. These bugs split the egg shell longitudinally and upon 
hatching cast an embryonic molt which bears a shiny black “egg burster.” 
This lies on the cephalic end between the eyes. It is figured on Plate XV. 
It has not ben noted heretofore by our American workers. Brocher has 
mentioned it for the European form. This very transparent, flimsy, deli- 
cate molt serves but the one purpose, that of aiding the bug to emerge. 
Bueno describes it as “a diapnanous pellicle, very soft and hairy, so soft 
that it does not retain its shape at all and is nearly invisible on the sur- 
face of the water.” Bueno considers it in the nature of an amnion. It 
shows the 1-segmented tarsi, subapical claws, tibial combs on all the legs. 
In case the bug hatches under water it swims about until it can attain 
the surface. 
Behavior. The new bugs resemble little spiders and jump about with 
the greatest alacrity. 
Number of Instars. There are five instars. Each instar lasts about 
a week. 
Food Habits. Predaceous upon insects, such as midges, and Noto- 
nectid nymphs, coming to the surface from below, and Jassids or other 
insects cast upon the water. About a drying pond they were feeding upon 
snails left stranded upon the ooze. It sometimes required maneuvering 
to pry the snail free from its support. 
Dr. C. F. Curtis Riley of Syracuse University gives splendid notes on 
behavior. See Am. Nat., October to December, 1919. 
DESCRIPTION OF STAGES. 
The Egg. 
| Shape “Long cylindrical, rounded at both ends and slightly concave 
at micropylar end. There is one micropyle and the chorion is somewhat 
thickened at this end.”—Bueno. 
Color. White when first deposited, becoming amber as red eye spots 
appear. 
Beuno has so recently published in an available periodical the descrip- 
tions of the instars that they are not reproduced here. (See Ent. News, 
May, 1917.) 
Gerris orba Stal. 
This species has been the subject of behavior studies by Essenberg. 
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