Marsh & McLennan Cos. Inc. announced today it will merge the defined contribution administration business of Putnam Investments and Mercer Human Resources Outsourcing; the combined firm will use the Mercer name. Brian Storms, newly appointed vice chairman of Mercer Human Resource Consulting, will oversee the organization. The U.S. business will be led by Dave Carlson, current national practice leader for human resources outsourcing at Mercer Human Resource Consulting. The combined firm will offer outsourcing for defined benefit plan administration, defined contribution plan administration, health and group administration and other human resources services. Barbara Perlmutter, an MMC spokeswoman, did not return calls seeking comment.