diff --git a/src/proc/mobject/session/placement-index-query-resolver.cpp b/src/proc/mobject/session/placement-index-query-resolver.cpp
index 86b2245d7..eb7e9686b 100644
--- a/src/proc/mobject/session/placement-index-query-resolver.cpp
+++ b/src/proc/mobject/session/placement-index-query-resolver.cpp
@@ -253,14 +253,14 @@ namespace session {
     /** use filter predicate provided by the concrete query */
     template<typename QUERY>
     ContentFilter
-    getContentFilter (QUERY query)
+    getContentFilter (QUERY const& query)
     {
       return query.contentFilter();
     }
     
     /** especially queries for MObjects need not be filtered */
     ContentFilter
-    getContentFilter (ScopeQuery<MObject>)
+    getContentFilter (ScopeQuery<MObject> const&)
     {
       static ContentFilter acceptAllObjects = bind (&acceptAllObjects_, _1);
       return acceptAllObjects;
@@ -342,7 +342,7 @@ namespace session {
     
     ScopeQuery<MO> const& query = static_cast<ScopeQuery<MO> const&> (goal);
     ScopeQueryKind direction = query.searchDirection();
-    PID scopeID = query.searchScope().getID();     ///////////////////////////////TICKET #411
+    PID scopeID = query.searchScope();
     
     return new ResultSet( bind (&PlacementIndexQueryResolver::setupExploration, 
                                 this, scopeID, direction)
diff --git a/src/proc/mobject/session/scope-query.hpp b/src/proc/mobject/session/scope-query.hpp
index 9e91fa9fc..8568a72da 100644
--- a/src/proc/mobject/session/scope-query.hpp
+++ b/src/proc/mobject/session/scope-query.hpp
@@ -116,7 +116,7 @@ namespace session {
       
       
       QueryResolver const&    index_;
-      PlacementMO const& startPoint_;
+      PlacementMO::ID    startPoint_;
       ScopeQueryKind    to_discover_;
       
     public:
@@ -142,7 +142,7 @@ namespace session {
           return _Query::resolveBy (index_);
         }
       
-      PlacementMO const&
+      PlacementMO::ID const&
       searchScope ()  const
         {
           return startPoint_;