def METHOD_NAME( species, old_Ntot, new_Ntot ):
    """
    If `species` is tracked, then generate new ids, between the
    indices `old_Ntot` and `new_Ntot` of the particle ID arrays
    (This is performed either on GPU or CPU.)
    """
    if species.tracker is not None:
        if species.use_cuda:
            species.tracker.generate_new_ids_gpu( old_Ntot, new_Ntot )
        else:
            species.tracker.id[old_Ntot:new_Ntot] = \
                species.tracker.METHOD_NAME( new_Ntot - old_Ntot )