subroutine seed(iseed)                                            
      common /ranfbk/iy                                                 
      if(iseed.le.-99) then                                             
         mype=ipet3e()
         mst=mstime(dum)                                                
c        iy=mst+int(1000.*secnds(0.))+345672197                         
         iy=mst+int(100.*(10.+mype)*secnds(0.))+345672197
         write(8,*)'T3E PE ',mype
         write(8,*)'seed changed into ',iy                              
      else                                                              
         iy=iseed                                                       
         write(8,*)'starting seed is',iy                                
      end if                                                            
      return                                                            
      end