aa. Occur intracytoplasmically as scattered growth. Genus III. Ricolesia, p. 959. 2. Pleomorphic forms large (2 microns). Apparently non-pathogenic; may be sapro- phytic. Genus IV. Colettsia, p. 961. II. Cultivable in chicken embryonic tissues. Genus V. Miyagawanella, p. 961. Genus I. Chlamydia Rake, 1956.* {Prowazekia Coles, Ann. New York Acad. Sci., 56, 1953, 461; not Prowazekia Hartmann and Chagas, Mem. Inst. Oswaldo Cruz, 1910, 89 (a protozoan genus).) Chla.my'di.a. Gr. fem.n. chlamys, chlamydis a cloak; M.L. fem.dim.n. Chlamydia a small cloak. Coccoid and spherical cells with a developmental cycle. Gram-negative. Occur intracyto- plasmically. Non-cultivable in chicken embryonic tissues. Have not yet been cultivated in tissue culture. Susceptible to the action of sulfonamides and of antibiotics. Cause ophthal- mic and urogenital diseases in man; transferable to other primates. In the previous edition of the Manual (Manual, 6th ed., 1948, 1114), the generic name Chlamydozoon von Prowazek (incorrectly attributed in Manual {loc. cit.) to Halberstaedter and von Prowazek, Arb. a. d. kaiserl. Gesundheitsamte, 26, 1907, 44) was used for this group of organisms. However, it has been shown (Buchanan, Internat. Bull, of Bact. Nomen. and Taxon., 5, 1955, 121) that Chlamydozoon is not available as a generic name for these organ- isms because its type species, Chlamydozoon bombycis von Prowazek, was presumably a virus, not a member of the family Chlamydiaceae. The type species is Chlamydia trachomatis (Busacca) Rake. Key to the species of genus Chlamydia. I. Causes trachoma in man. 1. Chlamydia trachomatis. II. Causes inclusion conjunctivitis in man. 2. Chlamydia oculogtenialis . 1. Chlamydia trachomatis (Busacca, are also found. All larger forms are encap- 1935) Rake, comb. nov. (Rickettsia trachomae sulated with a substance derived either (sic) Busacca, Arch. Ophthalm., 52, 1935, from the cell or from the cytoplasm of the b&lRickettsia trachomatis Yoey and Ysivvot, parasitized cells. The elementary body is Compt. rend. Soc. Biol., Paris, 12^, 1937, the basic unit. Occurs in pairs or in clus- 230; also see Arch. Inst. Past. d'Algerie, ters. Non-motile. Stains poorly with aniline 15, 1937, 339; Chlamydozoon trachomatis dyes, blue or reddish blue with Giemsa's Moshkovskiy, Uspekhi Souremennoi Biolo- stain and red or blue, depending on the gii, 19, 1945, 12.) metabolic state, with Macchiavello's stain. tra.cho'ma.tis. Gr. noun trachoma rough- The matrices of the plaques give a strong ness; M.L. noun trachoma trachoma; M.L. reaction for glycogen. Gram-negative, gen. noun trachomatis of trachoma. Cultivation: Has never been cultivated. Coccoid cells. Small cells 200 to 350 milli- Immunology: Possesses one or more anti- microns in diameter are the elementary gens in common with or closely resembling bodies. Initial bodies up to 800 millimicrons one or more of those present in Miyagawa- in diameter and plaques up to 10 microns nella spp. Produces, in low concentrations,
- The first appearance of the name Chlamydia in bacteriological literature (Jones, Rake
and Stearns, Jour. Inf. Dis., 76, 1945, 55) was as a nomen nudum, and as such the generic name Chlamydia Jones et al. has no standing.
