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from eggs of Oxycera Aug. 1902 found on an umbelliferous 
plant on the banks of Fuur Søen. Frequently bred from 
the rolled birch leaves containing eggs of Rhynchites be- 
tule. These eggs were collected for the sake of Ophio- 
neurus, but Trichogramma was also bred from them; 
for instance 16/, 06 bred from rolled leaves collected at 
Prestevang */, 06, bred */, 03 from same locality. 
Also caught on birch and alder as for instance 2°/, 05 
Ermelund on alder. Bred */, 05 from eggs of Chrysops, 
collected on Alisma leaves in Fonstrup Dam, Grib Skov; 
from Chrysops eggs from Fuglsangsöen, Dyrehaven on 
Typha latifolia, from Chrysops eggs from Rude Hegn 5/, — 10. 
Bred from Chrysops eggs nearly always together with a 
Proctotrypid. From Sialis eggs from nearly all localities 
where looked for near water. The eggs of Sialis are 
found in this country most frequently in the beginning 
of June. On Phragmites growing in the brook which runs 
through Bidstrup Fen near Roskilde in the early part of 
June is to be found a very great quantity of Sialis eggs. 
On these egg bunches the female 7richogramma can be 
found laying their eggs, and I have found as many as 
eight females on the same leaf. It is especially from these 
eggs that the apterous form of the male is bred. The 
males emerge first and wait faithfully for the females that 
emerge from one to two days later, when pairing takes 
place at once. As the individuals are not from the same 
parents as a rule, no aversion to pairing apparently is 
present. The males are absolutely prevented from coming 
away from the Phragmites plants, which are growing in 
the middle of the running water. When bred from Lepi- 
dopterous eggs found on land the apterous form of the 
male is exceedingly rare, whilst the winged form is very 
common, thus the reverse to those which are parasites on 
the Sialis eggs in wet places. It is therefore necessary 
that the sexes can find each other on the land, whilst 
there is no actual searching necessary on waterplants. 
