Are you talking about the blue RSS button at the end of the address bar or the stuff in the Bookmarks bar positioned below the address bar? The blue RSS button cannot be removed. To remove items from the Bookmarks bar you can right-click or control click on the item(s) and select delete, or you can click on the book icon in the bar itself, highlight the Bookmarks bar in the sidebar on the left, then do the same deletion from there.