This colorized transmission electron micrograph (TEM) of an ultra-thin specimen revealed some of the ultrastructural morphologic features seen in 1918 influenza virus virions. The prominent surface projections on the virions are composed of either the hemagglutinin, or neuraminidase type of glycoproteins. Composed of what looked like dots or tubules, was a dense envelope known as a 揷apsid?, which surrounded each virion抯 nucleic acid constituents.