diff --git a/Trajectories/trajectories.py b/Trajectories/trajectories.py
index 0f09d3fc784a23ddc054462c8c25769a1e5f5494..63a1ccab25fa9b2e9642e52ea3c653e80bdb9332 100755
--- a/Trajectories/trajectories.py
+++ b/Trajectories/trajectories.py
@@ -90,7 +90,7 @@ for i in ind_cf:
             segment = int(g.vertex_properties.name[target])
             traj_segm[traj_prop[target]].append(segment)
             inst_eddies = list(g.vertex_properties.inst_eddies[target])
-            expanded_traj[traj_prop[source]].extend(inst_eddies)
+            expanded_traj[traj_prop[target]].extend(inst_eddies)
 
 # Create trajectories for isolated segments:
 for v in g.vertices():