mongoose .push documentos incrustados en un modelo incrustado?

Would like to .push fields of an embedded structure into an embedded model document on a .push method. http://mongoosejs.com/docs/2.7.x/docs/embedded-documents.html

The console errors this though: SyntaxError: Unexpected token .

..for pushing bar.this : req.body.this, when concatenating for the embed in the embedded model

The models look like this:

var OneModel    = new Schema({
    foo: String,
    bar: {
      this : String,
      that : Number,
    }
});

var TwoModel    = new Schema({
    foo: String,
    bar: {
      this : String,
      that : Number,
    },
    modelone: [OneModel]
});

And the NodeJS API looks this:

var ModelsOneTwo = require('./app/models/modelsonetwo');

router.route('/modeltwo/:modeltwo_id')

    // update TwoModel with this _id
    //(accessed at PUT http://localhost:4200/api/v1/modeltwo/:modeltwo_id)
    .put(function(req, res) {

        ModelsOneTwo.findById(req.params._id, function(err, modeltwo) {

            if (err)
                res.send(err);

            // embedded document updating
            // http://mongoosejs.com/docs/2.7.x/docs/embedded-documents.html
            modeltwo.modelone.push({

                foo : req.body.foo,             
                bar.this : req.body.this,
                bar.that : req.body.that

            });

            // save the modeltwo, and check for errors
            modeltwo.save(function(err) {

                if (err)
                    res.send(err);

            res.json({ message: req.params.modeltwo_id + ' ' + req.body.foo });

            });

        });

    });