Measurement of the virtual photon structure function in                       
           Photon-Photon Collisions at LEP                                     
  
 The virtual photon structure function is extracted from a                     
 measurement of the cross section for the process                              
 e+e- -> e+e- gamma*gamma* -> e+e-X, where X denotes the                       
 hadronic final state, using the OPAL detector based on data                   
 from the 1998 LEP run. The scattered electrons have been                      
 tagged in the OPAL luminometers. The upgrade of four                          
 calorimeter modules in the very forward region at OPAL                        
 (z=7.8m) allows to study the virtual structure of the photon                  
 for 0.1 < P^2 < 1.0 GeV^2. The results are compared to Monte                  
 Carlo models using different descriptions of the P^2                          
 suppression of the photon.                                                    
  
 Parallel session : 3<br>2             
 Plenary  session :11<br>12