diff --git a/wxPython/wx/lib/ogl/_basic.py b/wxPython/wx/lib/ogl/_basic.py
index a8abcd5f54..320329a8e4 100644
--- a/wxPython/wx/lib/ogl/_basic.py
+++ b/wxPython/wx/lib/ogl/_basic.py
@@ -963,7 +963,7 @@ class Shape(ShapeEvtHandler):
             if line in linesAtThisAttachment:
                 # Done this one
                 del linesAtThisAttachment[linesAtThisAttachment.index(line)]
-                self._lines.Append(line)
+                self._lines.append(line)
 
         # Now add any lines that haven't been listed in linesToSort
         self._lines += linesAtThisAttachment