Many laboratory and clinical investigators have had difficulty in recognizing the different colony types of Neisseria gonorrhoeae as displayed in black and white photographs. Because of this problem, color photographs have been produced that we believe contribute to a better understanding of the colony types.
(JAMA 228:862-863, 1974)
Brown WJ, Kraus SJ. Gonococcal Colony Types. JAMA. 1974;228(7):862–863. doi:10.1001/jama.1974.03230320032024