Both J. W. Dawson and G. M. Dawson, father and son, wrote about glaciation in Canada in the late nineteenth century, but their philosophies and contributions often are misidentified. J. W. Dawson was a proponent of the deposition of glacial drift from floating ice, but believed that ice caps covered some highland areas. Hisson, G. M. Dawson, was indoctrinated with the floating ice theory, but his field studies in western Canada convinced him that glaciers deposited most of the drift there. Both the Cordilleran and Laurentide Ice Sheets were named by him. He reserved final judgement concerning the origin of the drift on the prairies because it contained foraminifera that he correctly identified as Cretaceous, but which an English micropaleontologist, considered to be an expert on Cretaceous forms, misjudged to be recent forms.