diff --git a/cartographer/mapping/map_builder.cc b/cartographer/mapping/map_builder.cc
index 5e1207f..8d4b1ba 100644
--- a/cartographer/mapping/map_builder.cc
+++ b/cartographer/mapping/map_builder.cc
@@ -138,8 +138,8 @@ string MapBuilder::SubmapToProto(const int trajectory_id,
   }
 
   response->set_submap_version(submaps->Get(submap_index)->num_range_data);
-  submaps->SubmapToProto(submap_index, sparse_pose_graph_->GetTrajectoryNodes(),
-                         submap_transforms[submap_index], response);
+  submaps->SubmapToProto(submap_index, submap_transforms[submap_index],
+                         response);
   return "";
 }
 
diff --git a/cartographer/mapping/sparse_pose_graph_test.cc b/cartographer/mapping/sparse_pose_graph_test.cc
index a2224c5..c427edb 100644
--- a/cartographer/mapping/sparse_pose_graph_test.cc
+++ b/cartographer/mapping/sparse_pose_graph_test.cc
@@ -34,8 +34,7 @@ class FakeSubmaps : public Submaps {
 
   int size() const override { LOG(FATAL) << "Not implemented."; }
 
-  void SubmapToProto(int, const std::vector<mapping::TrajectoryNode>&,
-                     const transform::Rigid3d&,
+  void SubmapToProto(int, const transform::Rigid3d&,
                      proto::SubmapQuery::Response*) const override {
     LOG(FATAL) << "Not implemented.";
   }
diff --git a/cartographer/mapping/submaps.h b/cartographer/mapping/submaps.h
index 17609a6..332d8b8 100644
--- a/cartographer/mapping/submaps.h
+++ b/cartographer/mapping/submaps.h
@@ -113,10 +113,9 @@ class Submaps {
   virtual int size() const = 0;
 
   // Fills data about the Submap with 'index' into the 'response'.
-  virtual void SubmapToProto(
-      int index, const std::vector<mapping::TrajectoryNode>& trajectory_nodes,
-      const transform::Rigid3d& global_submap_pose,
-      proto::SubmapQuery::Response* response) const = 0;
+  virtual void SubmapToProto(int index,
+                             const transform::Rigid3d& global_submap_pose,
+                             proto::SubmapQuery::Response* response) const = 0;
 
  protected:
   static void AddProbabilityGridToResponse(
diff --git a/cartographer/mapping/trajectory_node.h b/cartographer/mapping/trajectory_node.h
index 5c78efd..f0cf70a 100644
--- a/cartographer/mapping/trajectory_node.h
+++ b/cartographer/mapping/trajectory_node.h
@@ -58,14 +58,6 @@ struct TrajectoryNode {
   transform::Rigid3d pose;
 };
 
-// Users will only be interested in 'trajectory_nodes'. But 'constant_data'
-// is referenced by 'trajectory_nodes'. This struct guarantees that their
-// lifetimes are bound.
-struct TrajectoryNodes {
-  std::deque<mapping::TrajectoryNode::ConstantData> constant_data;
-  std::vector<mapping::TrajectoryNode> trajectory_nodes;
-};
-
 }  // namespace mapping
 }  // namespace cartographer
 
diff --git a/cartographer/mapping_2d/submaps.cc b/cartographer/mapping_2d/submaps.cc
index a05b782..1ea41a2 100644
--- a/cartographer/mapping_2d/submaps.cc
+++ b/cartographer/mapping_2d/submaps.cc
@@ -135,8 +135,7 @@ const Submap* Submaps::Get(int index) const {
 int Submaps::size() const { return submaps_.size(); }
 
 void Submaps::SubmapToProto(
-    const int index, const std::vector<mapping::TrajectoryNode>&,
-    const transform::Rigid3d&,
+    const int index, const transform::Rigid3d&,
     mapping::proto::SubmapQuery::Response* const response) const {
   AddProbabilityGridToResponse(Get(index)->local_pose(),
                                Get(index)->probability_grid, response);
diff --git a/cartographer/mapping_2d/submaps.h b/cartographer/mapping_2d/submaps.h
index 30771c6..b536127 100644
--- a/cartographer/mapping_2d/submaps.h
+++ b/cartographer/mapping_2d/submaps.h
@@ -58,8 +58,7 @@ class Submaps : public mapping::Submaps {
   const Submap* Get(int index) const override;
   int size() const override;
   void SubmapToProto(
-      int index, const std::vector<mapping::TrajectoryNode>& trajectory_nodes,
-      const transform::Rigid3d& global_submap_pose,
+      int index, const transform::Rigid3d& global_submap_pose,
       mapping::proto::SubmapQuery::Response* response) const override;
 
   // Inserts 'range_data' into the Submap collection.
diff --git a/cartographer/mapping_3d/submaps.cc b/cartographer/mapping_3d/submaps.cc
index 7aa764c..79345c0 100644
--- a/cartographer/mapping_3d/submaps.cc
+++ b/cartographer/mapping_3d/submaps.cc
@@ -239,8 +239,7 @@ const Submap* Submaps::Get(int index) const {
 int Submaps::size() const { return submaps_.size(); }
 
 void Submaps::SubmapToProto(
-    int index, const std::vector<mapping::TrajectoryNode>& trajectory_nodes,
-    const transform::Rigid3d& global_submap_pose,
+    int index, const transform::Rigid3d& global_submap_pose,
     mapping::proto::SubmapQuery::Response* const response) const {
   // Generate an X-ray view through the 'hybrid_grid', aligned to the xy-plane
   // in the global map frame.
diff --git a/cartographer/mapping_3d/submaps.h b/cartographer/mapping_3d/submaps.h
index 55fba95..c32b8ae 100644
--- a/cartographer/mapping_3d/submaps.h
+++ b/cartographer/mapping_3d/submaps.h
@@ -67,8 +67,7 @@ class Submaps : public mapping::Submaps {
   const Submap* Get(int index) const override;
   int size() const override;
   void SubmapToProto(
-      int index, const std::vector<mapping::TrajectoryNode>& trajectory_nodes,
-      const transform::Rigid3d& global_submap_pose,
+      int index, const transform::Rigid3d& global_submap_pose,
       mapping::proto::SubmapQuery::Response* response) const override;
 
   // Inserts 'range_data' into the Submap collection.