Roselyn H. Spencer was named executive director of the $1.2 billion City of Baltimore Employees' Retirement System, said Joan Pratt, chairwoman. Ms. Spencer had been acting executive director since July, when the plan's management was separated from that of the $1.8 billion City of Baltimore Fire and Police Employees' Retirement System. Previously, while the plans were independent of each other, the management was shared. Ms. Spencer was deputy administrator when the plans shared the same staffs; Thomas P. Taneyhill, former executive administrator of the jointly managed plans, became executive director of the Fire and Police system in July. The title of executive administrator was eliminated at that time.