The process whose specific outcome is the progression of the glomerular epithelium over time, from its formation to the mature structure. The glomerular epithelium is an epithelial tissue that covers the outer surfaces of the glomerulus. The glomerular epithelium consists of both parietal and visceral epithelium. Metanephric glomerular parietal epithelial cells are specialized epithelial cells that form tight junctions as a barrier to protein transport. A metanephric glomerular visceral epithelial cell is a specialized epithelial cell that contains 'feet' that interdigitate with the 'feet' of other glomerular epithelial cells in the metanephros. [ GOC:mtg_kidney_jan10 ]