diff --git a/grudge/symbolic/mappers/__init__.py b/grudge/symbolic/mappers/__init__.py
index ba3064f6c5edba555ad2027218c6bef8881ba135..dbaae3a7305ae1bfe4fddc00bf02d5719c7d777e 100644
--- a/grudge/symbolic/mappers/__init__.py
+++ b/grudge/symbolic/mappers/__init__.py
@@ -675,7 +675,7 @@ class StringifyMapper(pymbolic.mapper.stringifier.StringifyMapper):
     # }}}
 
     def map_ones(self, expr, enclosing_prec):
-        return "Ones" + self._format_op_props(expr)
+        return "Ones:" + self._format_dd(expr.dd)
 
     # {{{ geometry data