part of neuromast primordium migration posterior lateral line development posterior lateral line neuromast primordium migration GO:0048920 PLL neuromast primordium migration The migration of a relatively undifferentiated cell along the developing posterior lateral line, originating from cranial ectodermal placodes situated behind the ear. The neuromast primordium deposits proneuromasts along the lateral line, from which the neuromasts will develop. biological_process