diff --git a/rdflib/collection.py b/rdflib/collection.py
index 14351f95b..3983c1758 100644
--- a/rdflib/collection.py
+++ b/rdflib/collection.py
@@ -85,9 +85,6 @@ def __len__(self):
         count = 0
         links = set()
         for item in self.graph.items(self.uri):
-            assert item not in links, \
-                "There is a loop in the RDF list! " + \
-                "(%s has been processed before)" % item
             links.add(item)
             count += 1
         return count
diff --git a/test/test_issue223.py b/test/test_issue223.py
index 378b7db0b..8a05da88a 100644
--- a/test/test_issue223.py
+++ b/test/test_issue223.py
@@ -12,6 +12,7 @@ def test_collection_with_duplicates():
     for _,_,o in g.triples((URIRef("http://example.org/s"), URIRef("http://example.org/p"), None)):
         break
     c = list(Collection(g, o))
+    assert c == list(URIRef("http://example.org/" + x) for x in ["a", "b", "a"])
 
 if __name__ == '__main__':
     test_collection_with_duplicates()