Ember Data: model.get('modelName') is undefined, but model._internalModel works

I'm using Ember Data 2.2.0 and Ember 2.2.1. After retrieving a model from the data store, I'd like to get the model's type name as a string.

According to the API Docs, DS.Model defines a modelName property, which looks like what I want. However, I find that model.modelName, and model.get('modelName')are undefined, after retrieving model from the store with findRecord.

On the other hand, model._internalModel.modelName returns the lowercased, dasherized name of the model, as expected.

What's going on here?