Why do Content and Prototype cells not appear for tables views in Xibs?

I am moving a UIViewController from the main storyboard to a xib file to make it easier to reuse. The main control on it is UITableView. But in the original on the storyboard there are 2 properties that I used to set up the table view - Content, and Prototype Cells - which are just not there in the Xib.


What is going on?