Uncaught TypeError: Object #<Object> has no method 'get'

ListingCollection = Backbone.Collection.extend({
    model: Listing,
    url: '/api/search_by_bounds',

    fetchNew: function(options) {
        options = options || {};
        var collection = this,
            success = options.success;
        options.success = function(resp, status, xhr) {
            _(collection.parse(resp, xhr)).each(function(item) {
                // added this conditional block
                if (!collection.get(item.id)) {
                    collection.add(item, {silent:true});
                    new ListingMarkerView({ model:item }).render();
                }
            });
            if (!options.silent) {
                collection.trigger('reset', collection, options);
            }
            if (success) success(collection, resp);
        };
        return (this.sync || Backbone.sync).call(this, 'read', this, options);
    }
});

ListingMarkerView = Backbone.View.extend({

    render: function() {
        var marker = L.marker([this.model.get('lat'), this.model.get('lng')]);
        markers.addLayer(marker);
    },

    close: function() {
        this.unbind;
    }

});

my_collection.fetch({success: function(collection, resp){
    collection.reset(resp, {silent: true});
}});