Neis.se'ri.a. M.L. fem.n. Neisseria named for Dr. Albert Neisser, who discovered the organism causing gonorrhoea in 1879. Cocci occurring in pairs with the adjacent sides flattened. Gram-negative. Five species produce a yellow, a greenish yellow or a tan pigment. Growth on non-enriched media may be poor. Biochemical activities are limited. Few carbohydrates are utilized. Indole not produced. Nitrates not reduced. Catalase is abundantlj^ produced. Aerobic or facultatively anaerobic. Some species are hemolytic. Parasites of animals so far as known. The type species is Neisseria gonorrhoeae Trevisan. Key to the species of genus Neisseria. I. Grow best on special culture media containing blood, blood serum or similar enrichment fluids (especiallj^ with added glucose) at 35° to 37° C.; growth rare below 25° C. Non- chromogenic. A. Acid from glucose, not from maltose. Will grow anaerobically. 1. Neisseria gonorrhoeae. B. Acid from glucose and maltose. No growth anaerobically. 2. Neisseria meningitidis. II. Grow well on ordinary culture media at 22° C. A. Non-chromogenic. 1. No acid from any carliohydrate. Moist colonies on agar. From human nasal se- cretions. 3. Neisseria catarrhalis. 2. Acid from glucose, fructose, maltose and sucrose. a. Dry, crumbly colonies on agar. Sometimes hemolytic. 4. Neisseria sicca. aa. Growth slow and delicate. Hemolytic. 5. Neisseria haemolysans. B. Chromogenic, especially on Loeffler's serum medium or on Dorsett's egg medium*. 1. No acid from any carbohydrate. a. Greenish yellow chromogenesis. 6. Neisseria flavescens. aa. Light brown to tan chromogenesis. 7. Neisseria caviae. 2. Acid from carbohydrates. a. No acid from fructose. Greenish yellow chromogenesis. 8. Neisseria subflava. aa. Acid from fructose. b. No acid from sucrose. Greenish yellow chromogenesis. 9. Neisseria flava. bb. Acid from sucrose. Greenish yellow chromogenesis. 10. Neisseria perflava. 1. Neisseria gonorrhoeae Trevisan, dau, in Just's Bot. Jahresber., I Abt., 1885. (Micrococcus der Gonorrhoe, Neisser, Orig., 26, 1898, 100.) Vorl. Mitteil., Cent. f. Medicinische Wis- go.nor.rhoe'ae. Gr. noun gonorrhoea senchaft, 17, 1879, 497; Trevisan, Atti gonorrhea; M.L. gen. noun gonorrhoeae of della Accademia Fisio-Medico-Statistica in gonorrhea. Milano, Ser. 4, 3, 1885 105; Micrococcus Common name: Gonococcus. gonorrhoeae Fliigge, Die Mikroorganismen, Spheres, 0.6 to 1.0 micron in diameter, 2 Aufl., 1886, 156; Gonococcus neisseri Lin- occurring singly and in pairs, the sides flat-
- Abel's modification. See M. Levine and H. Schoenlein, A Compilation of Culture
Media. Baltimore, 1930, 792.
