الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
Certain aspects of the morphology and ecology of the most
common species of Gryllotalpa in Egypt were studied in the present
investigation and the results showed the following:
1- Different species of mole-crickets could be easily identified
by means of the fore-wings. These differ in measurments and in
the position and number of teeth of the sound production organ
on Cu2 vein. The fore wings were also proven to be the simplest
means for sorting out the sexes within each mole-cricket
species anrl sub-species.
2- Gryllotalpa gryllotalpa (L.) adults were attracted to light
traps in large numbers during the period extending from March
to September or October. The highest monthly catches occurred
during August and September at all five regions of this study
(Giza, Sharkia, Gharbia, Dakahlia and Beheira) where trapping
was conducted for 3 years, {1985, 86 and 87}.
The insects activity was affected in varying degrees by the prevailing
environmental factors of the day maximum, night minimum
temperature, soil temperature (at 10 and 20 em deep), the day mean
relative humidity and rainfall. Analysis of variance has shown
that 85.4 % - 97.2 % of the variability in trap catches, henc the
activity of mole crickets, could be accounted for by the tested
factors.
3- The ”new” type of pitfall-traps (devolped in this investiga
t ion) was superior to the Willcocks type ( used by Willcocks,
1925) in sampling mole-crickets.
4- Pitfall traps caught more mole-cricket individuals and species
than light traps. Species of mole-crickets sampled at Giza for
a whole year (1987) using pitfall traps were G. gryllotalpa, G.
gryl10talpa ssp. cophta. G. africana and G. Africana ssp.
cophta.
5- Winter crops are less infested by mole-crickets than autumn,
spring and summer crops. The level of infestation within a
certain crop differs according to the kind of crop growing before
it in the rotation system.