diff --git a/tests/types_test.py b/tests/types_test.py
index 8f120931..8e441c65 100644
--- a/tests/types_test.py
+++ b/tests/types_test.py
@@ -16,6 +16,11 @@ from mitogen.core import b
 import testlib
 
 
+####
+#### see also message_test.py / PickledTest
+####
+
+
 class BlobTest(testlib.TestCase):
     klass = mitogen.core.Blob