diff --git a/lib/psych/visitors/yaml_tree.rb b/lib/psych/visitors/yaml_tree.rb
index ff0fcd20..44e6980f 100644
--- a/lib/psych/visitors/yaml_tree.rb
+++ b/lib/psych/visitors/yaml_tree.rb
@@ -71,7 +71,7 @@ def initialize emitter, ss, options
 
           method = respond_to?(method) ? method : h[klass.superclass]
 
-          raise(TypeError, "Can't dump #{target.class}") unless method
+          raise(TypeError, "can't dump #{klass.name}") unless method
 
           h[klass] = method
         end