[ by Melanie Gretchen ] Barclays' short list is just getting shorter as it seeks to replace the roles of CEO and chairman after the resignation of former CEO Robert Diamond Jr., and chairman Marcus Agius.  Amid the on-going investigation into the manipulation of Libor, for which Barclays paid $453 million to settle, Michael Rake, the deputy chairman, withdrew himself from consideration as the next chairman, according to a regulatory filing on Monday. The CFTC and Britain's Financial Services Authority alleged that the bank submitted false rates to improve profits and deflect scrutiny about its financial health.  However, rather than quieting public and shareholder outrage over the company's compensation and governance, the settlement has fueled the fire [CI Note: In other words, the next leadership figures should have stellar reputations or be able to create a new image into which Barclays can grow.] For this reason, shareholders' preference may lead toward an outsider stepping to head Barclays.  Nevertheless, speculation has surrounded Rich Ricci, the current head of its investment banking unit, to assume the role of CEO – despite the the fact that he was part of the senior leadership when the rate manipulation occurred [CI Note: How many other current, potentially negligent Barclays heads were tapped to lead?].  As far as Mr. Ricci concerned, the question of potential is moot: on Sunday, he took himself out of the running, according to John Sutherland, the non-executive director heading the search. It looks like Mr. Sutherland has his work cut out for him. For further details, go to: [Dealbook,7/23/12] and [Fox Business, 7/22/12].