The grim reaper visited Harper Collins this morning – and heads are still rolling. Steve Ross, President and Publisher of Collins, and Lisa Gallagher, head of the William Morrow group, are gone, along with other top execs and a “small percentage” of staff. Last week, it was reported that in the final quarter of 2008, sales dropped 25 percent. The publishing giant, owned by Rupert Murdoch’s News Corp., will close the Collins Division and “realign” the imprints by folding general non-fiction books into the Harper imprint. Collins Business will be published as Harper Business, and Collins trade paperbacks are getting folded into Harper Perennial and Harper Paperbacks. “In 2009 and beyond, while continuing to take risks, we have to be more diligent in managing costs” President and Group Publisher Michael Morrison wrote in a company-wide e-mail this morning.