diff --git a/tardis/gui/widgets.py b/tardis/gui/widgets.py
index 06036dcc9c6..fe13b70a122 100644
--- a/tardis/gui/widgets.py
+++ b/tardis/gui/widgets.py
@@ -959,7 +959,7 @@ def __init__(self, line_interaction_analysis, atom_data, lines_data, description
         self.layout = QtGui.QHBoxLayout()
         self.line_interaction_analysis = line_interaction_analysis
         self.atom_data = atom_data
-        self.lines_data = lines_data.reset_index().set_index('line_data')
+        self.lines_data = lines_data.reset_index().set_index('line_id')
         line_interaction_species_group = \
         line_interaction_analysis.last_line_in.groupby(['atomic_number', 
             'ion_number'])