diff --git a/Stream_lines_2/include/CGAL/Euler_integrator_2.h b/Stream_lines_2/include/CGAL/Euler_integrator_2.h
index 09bc19bedd4..365d8e76ba3 100644
--- a/Stream_lines_2/include/CGAL/Euler_integrator_2.h
+++ b/Stream_lines_2/include/CGAL/Euler_integrator_2.h
@@ -82,7 +82,7 @@ Euler_integrator_2<Vector_field>::Euler_integrator_2(const FT & integration_step
 template <class Vector_field>
 inline typename Euler_integrator_2<Vector_field>::Point_2 
 Euler_integrator_2<Vector_field>::operator()
-  (const Point_2 & p, const Vector_field_2 & vector_field_2, const FT & integration_step, Vector_2 v, const bool & index) const
+  (const Point_2 & p, const Vector_field_2 & , const FT & integration_step, Vector_2 v, const bool & index) const
 {
   if (!index)
     {
diff --git a/Stream_lines_2/include/CGAL/Regular_grid_2.h b/Stream_lines_2/include/CGAL/Regular_grid_2.h
index 812f2a5a679..d107ebfaa3f 100644
--- a/Stream_lines_2/include/CGAL/Regular_grid_2.h
+++ b/Stream_lines_2/include/CGAL/Regular_grid_2.h
@@ -198,8 +198,8 @@ Regular_grid_2<StreamLinesTraits_2>::get_vector_field(const Point_2 &
 
 template <class StreamLinesTraits_2>
 typename Regular_grid_2<StreamLinesTraits_2>::FT
-Regular_grid_2<StreamLinesTraits_2>::get_density_field(const Point_2 &
-						       p) const
+Regular_grid_2<StreamLinesTraits_2>::get_density_field(const Point_2 & ) const
+						       
 {
   return 1.0;
 }
@@ -207,8 +207,7 @@ Regular_grid_2<StreamLinesTraits_2>::get_density_field(const Point_2 &
 template<class StreamLinesTraits_2>
 inline
 typename Regular_grid_2<StreamLinesTraits_2>::FT
-Regular_grid_2<StreamLinesTraits_2>::get_integration_step(const
-							  Point_2 &)
+Regular_grid_2<StreamLinesTraits_2>::get_integration_step(const Point_2 &)
   const
 {
   return 1.0;