{
    // Simply add the collection to the list.
    //
    if (index == CommandParameter.NO_INDEX)
    {
      ownerList.addAll(collection);
    }
    else
    {
      ownerList.addAll(index, collection);
    }

    // Update the containing map, if necessary.
    //
    updateEMap(owner, feature);

    // We'd like the collection of things added to be selected after this command completes.
    //
    affectedObjects = collection;
  }