958 ORDER I. RICKETTSIALES 



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&l\Rickettsia trachomatis Yo\ey 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. 



