Clicking "Add Parent" to select a suitable parent publication when adding a new publication, a popup window appears which immediately closes. Replicated in IE 10, IE 11, Chrome 31.0.1650.63. Is there a bug or has the mechanism changed for creating a blueprint?
By default creating a publication will only add a Building Block folder and Categories and Keyword and it will require you to Create a Structure Group manually. For a publication to act as a parent (or Base) it must have a Root structure group.
One day, I will remember to create the Root SG in the base!