Gram stain of Staphylococcus aureus showing gram-positive cocci in pairs, tetrads, and clusters. Original magnification ×1000. (Courtesy of L Ching.) Source: The Staphylococci, Jawetz, Melnick, & Adelberg’s Medical Microbiology, 27e Citation: Carroll KC, Hobden JA, Miller S, Morse SA, Mietzner TA, Detrick B, Mitchell TG, McKerrow JH, Sakanari JA. Jawetz, Melnick, & Adelberg’s Medical Microbiology, 27e; 2015 Available at: http://accesspharmacy.mhmedical.com/DownloadImage.aspx?image=/data/books/1551/car_ch13_f001.png&sec=94106633&BookID=1551&ChapterSecID=94106626&imagename= Accessed: December 28, 2017 Copyright © 2017 McGraw-Hill Education. All rights reserved