diff --git a/Core/PythonAPI/src/ParticleBuilder.pypp.cpp b/Core/PythonAPI/src/ParticleBuilder.pypp.cpp
index 19d670c808ddb3ee51a8882d143416f6825068f9..2cd915ce0fd4f38a9278e3f6c5cce1550400afe6 100644
--- a/Core/PythonAPI/src/ParticleBuilder.pypp.cpp
+++ b/Core/PythonAPI/src/ParticleBuilder.pypp.cpp
@@ -37,7 +37,7 @@ void register_ParticleBuilder_class(){
             ParticleBuilder_exposer.def( 
                 "setPrototype"
                 , setPrototype_function_type( &::ParticleBuilder::setPrototype )
-                , ( bp::arg("particle"), bp::arg("name"), bp::arg("param"), bp::arg("nbr_samples"), bp::arg("sigma_factor")=0.0, bp::arg("scale")=1.0e+0 ) );
+                , ( bp::arg("particle"), bp::arg("name"), bp::arg("distribution"), bp::arg("nbr_samples"), bp::arg("sigma_factor")=0.0, bp::arg("scale")=1.0e+0 ) );
         
         }
     }