diff --git a/src/PlotlyEditor.js b/src/PlotlyEditor.js
index 7e553be97..5e7868711 100644
--- a/src/PlotlyEditor.js
+++ b/src/PlotlyEditor.js
@@ -106,7 +106,7 @@ class PlotlyEditor extends Component {
           this.props.onDeleteTrace(payload);
         }
         if (payload.traceIndexes && payload.traceIndexes.length) {
-          graphDiv.data.splice(payload[0], 1);
+          graphDiv.data.splice(payload.traceIndexes[0], 1);
           if (this.props.onUpdate) {
             this.props.onUpdate();
           }
diff --git a/src/components/fields/TraceSelector.js b/src/components/fields/TraceSelector.js
index 6538c45a8..353cdd581 100644
--- a/src/components/fields/TraceSelector.js
+++ b/src/components/fields/TraceSelector.js
@@ -52,7 +52,11 @@ class TraceSelector extends Component {
         'tonext',
       ];
     }
-
+    this.setTraceDefaults(
+      props.container,
+      props.fullContainer,
+      props.updateContainer
+    );
     this.setLocals(props, context);
   }
 
@@ -64,17 +68,26 @@ class TraceSelector extends Component {
     } else {
       this.traceOptions = [{label: 'Scatter', value: 'scatter'}];
     }
+    this.fullValue = plotlyTraceToCustomTrace(props.container);
+  }
 
-    this.fullValue = plotlyTraceToCustomTrace(props.fullContainer);
+  setTraceDefaults(container, fullContainer, updateContainer) {
+    if (!container.mode && fullContainer.type === 'scatter') {
+      updateContainer({
+        type: 'scatter',
+        mode: fullContainer.mode || 'markers',
+      });
+    }
   }
 
   componentWillReceiveProps(nextProps, nextContext) {
+    const {container, fullContainer, updateContainer} = nextProps;
+    this.setTraceDefaults(container, fullContainer, updateContainer);
     this.setLocals(nextProps, nextContext);
   }
 
   updatePlot(value) {
     const update = customTraceToPlotlyTrace(value);
-
     if (this.props.updateContainer) {
       this.props.updateContainer(update);
     }
@@ -97,6 +110,7 @@ TraceSelector.contextTypes = {
 
 TraceSelector.propTypes = {
   getValObject: PropTypes.func,
+  container: PropTypes.object.isRequired,
   fullContainer: PropTypes.object.isRequired,
   fullValue: PropTypes.any.isRequired,
   updateContainer: PropTypes.func,
diff --git a/src/components/fields/__tests__/DataSelector-test.js b/src/components/fields/__tests__/DataSelector-test.js
index 7a7f6d153..1ffae96dc 100644
--- a/src/components/fields/__tests__/DataSelector-test.js
+++ b/src/components/fields/__tests__/DataSelector-test.js
@@ -37,6 +37,7 @@ describe('DataSelector', () => {
   it('calls updatePlot with srcAttr and data when present', () => {
     const onUpdateTraces = jest.fn();
     const wrapper = render({onUpdateTraces}).find(DropdownWidget);
+    onUpdateTraces.mockClear();
     wrapper.prop('onChange')('y1');
     expect(onUpdateTraces.mock.calls[0][0]).toEqual({
       update: {xsrc: 'y1', x: [2, 3, 4]},
diff --git a/src/components/fields/__tests__/TraceSelector-test.js b/src/components/fields/__tests__/TraceSelector-test.js
index f7ea24edc..d9a189ee9 100644
--- a/src/components/fields/__tests__/TraceSelector-test.js
+++ b/src/components/fields/__tests__/TraceSelector-test.js
@@ -9,6 +9,67 @@ import {connectTraceToPlot} from 'lib';
 describe('TraceSelector', () => {
   const TraceSection = connectTraceToPlot(Section);
 
+  it('sets mode to markers if trace scatter, no data or mode provided', () => {
+    const editorProps = {
+      ...fixtures.scatter({data: [{mode: null, xsrc: null, ysrc: null}]}),
+      onUpdate: jest.fn(),
+    };
+    const wrapper = mount(
+      <TestEditor {...editorProps} plotly={plotly}>
+        <TraceSection traceIndex={0}>
+          <TraceSelector attr="type" />
+        </TraceSection>
+      </TestEditor>
+    ).find(TraceSelector);
+
+    const innerDropdown = wrapper.find(Dropdown);
+
+    expect(wrapper.props().plotProps.container.mode).toBe('markers');
+    expect(innerDropdown.prop('value')).toEqual('scatter');
+  });
+
+  it('if no data provided, but mode is provided, displays correct trace type', () => {
+    const editorProps = {
+      ...fixtures.scatter({
+        data: [{mode: 'lines+markers', xsrc: null, ysrc: null}],
+      }),
+      onUpdate: jest.fn(),
+    };
+    const wrapper = mount(
+      <TestEditor {...editorProps} plotly={plotly}>
+        <TraceSection traceIndex={0}>
+          <TraceSelector attr="type" />
+        </TraceSection>
+      </TestEditor>
+    ).find(TraceSelector);
+
+    const innerDropdown = wrapper.find(Dropdown);
+
+    expect(innerDropdown.prop('value')).toEqual('line');
+  });
+
+  it('if data provided, but no mode is provided, chooses mode according to fullData', () => {
+    const editorProps = {
+      ...fixtures.scatter(),
+      onUpdate: jest.fn(),
+    };
+
+    expect(!editorProps.graphDiv.data[0].mode).toBe(true);
+    expect(editorProps.graphDiv._fullData[0].mode).toBe('lines+markers');
+
+    const wrapper = mount(
+      <TestEditor {...editorProps} plotly={plotly}>
+        <TraceSection traceIndex={0}>
+          <TraceSelector attr="type" />
+        </TraceSection>
+      </TestEditor>
+    ).find(TraceSelector);
+
+    const innerDropdown = wrapper.find(Dropdown);
+    expect(wrapper.props().plotProps.container.mode).toBe('lines+markers');
+    expect(innerDropdown.prop('value')).toEqual('line');
+  });
+
   it('interprets scatter + fill as type=area', () => {
     const editorProps = {
       ...fixtures.scatter({data: [{fill: 'tonexty'}]}),