diff --git a/src/clos/builtin.lsp b/src/clos/builtin.lsp
index 6c3c2c132..0effca669 100644
--- a/src/clos/builtin.lsp
+++ b/src/clos/builtin.lsp
@@ -76,7 +76,7 @@
 (defmethod allocate-instance ((class structure-class) &rest initargs)
   (declare (ignore initargs))
   (apply #'si::make-structure class
-	 (make-list (class-size class)) :initial-element (si::unbound)))
+	 (make-list (class-size class) :initial-element (si::unbound))))
 
 (defmethod finalize-inheritance ((class structure-class))
   (call-next-method)