1. The aggregation pheromone ofIps duplicatus and its role in competitive interactions withI. typographus (Coleoptera: Scolytidae)

   • Fredrik Schlyter
   • Göran Birgersson
   • Alf Bakke

   OriginalPaper Pages: 103 - 112

2. Attraction of field-flying aphid males to synthetic sex pheromone

   • Jim Hardie
   • Stephen F. Nottingham
   • Lester J. Wadhams

   OriginalPaper Pages: 113 - 117

3. Some polyphagous Homoptera gain protection from their natural enemies by feeding on the toxic plantsSpartium junceum andErythrina corallodendrum (Leguminosae)

   • Zvi Mendel
   • Daniel Blumberg
   • Martin Weissenberg

   OriginalPaper Pages: 118 - 124

4. Toxicity and attraction effects produced byMorinda citrifolia fruits on theDrosophila melanogaster complex of species

   • Luc Legal
   • Jean R. David
   • Jean Marc Jallon

   OriginalPaper Pages: 125 - 129