diff --git a/prototype/UI/index.html b/prototype/UI/index.html
index 2a467d66a..0013be944 100644
--- a/prototype/UI/index.html
+++ b/prototype/UI/index.html
@@ -85,8 +85,8 @@
     }
 
     /// Term -> String -> DOM
-    function termToDOM(term, source) {
-        return rangeAndSyntaxToDOM(term.range, term.unwrap, source, function(term) { return term.range; }, function(term) { return termToDOM(term, source); });
+    function termToDOM(term, which, source) {
+        return rangeAndSyntaxToDOM(term.range, term.unwrap, source, function(term) { return term.range; }, function(term) { return termToDOM(term, which, source); });
     }
 
     /// Diff -> String -> String -> DOM