Negative stain of an enveloped virus with such short surface projections that they are not often visible in negative stains (rubella virus); the nucleocapsids inside are not morphologically distinct. Negative stain of an enveloped virus with such short surface projections that they are not often visible in negative stains (rubella virus); the nucleocapsids inside are not morphologically distinct. Some particles are outlined by the stain, showing the surface of the virus (arrow), and some are penetrated by the stain (arrowhead) allowing visualization of the interior of the virus. Bar, 100 nm. Magnification, ×100,000. (Reprinted from reference 56 with permission of John Wiley & Sons, Inc. Copyright 1986 Wiley-Liss, Inc., a subsidiary of John Wiley & Sons, Inc.)‏ Cynthia S. Goldsmith, and Sara E. Miller Clin. Microbiol. Rev. 2009; doi:10.1128/CMR.00027-09