diff --git a/pub/src/manip.cpp b/pub/src/manip.cpp
index 2e246e13f4bcb03e2cfe3d0312758f96a2f7bfc6..8369377b952df858ec7a7aa83c6c245882481e54 100644
--- a/pub/src/manip.cpp
+++ b/pub/src/manip.cpp
@@ -628,10 +628,9 @@ void NManip::ScaSelect( string del_or_ret )
     } else if ( del_or_ret=="r" ){
         action = "Retain";
         sel_ret = true;
-    } else{
-        cout << "FATAL: invalid del_or_ret\n";
-        return;
-    }
+    } else
+        throw string( "BUG: invalid del_or_ret" );
+
     CList JSel, JSelSorted;
     static string jSel = "";
     NOlm::JSelAsk( action + " which scans", &jSel, &JSel );