Editing content in cover

I'm having some trouble in admin finding the location of the content that shows in the cover area on each page.  In the designer module, I've replaced the default cover image but on the pages, there seems to be another element that is positioned in that same space.  For example, following installation, on the homepage,  we see the cover image, and it has text which reads:  "Unity is strength... when there is teamwork and collaboration, wonderful things can be achieved."  There's also a "join now" button under the text that launches a signup page if you're not logged in as a user.  How do I edit this?  Actually, I like the Join now button, but I wish to remove or change the text.  It almost seems like it's baked in, but it can't be?