SCHIZOMYCETES 



SCHIZOMYCETACEA Naegeli, 1857. 



Definition. — ^Thallophyta without chlorophyll and as a rule with- 

 out chromatophores, with the vegetative body consisting of a 

 single cell, in which the nucleus is not present in the form typical 

 for other thallophytes. Reproduction by fission or spore formation. 



Classification. — The Schizomycetes may be divided into orders 

 as follows: — 



A. Cells without sulphur or bacterio-purpurein — Order I., Eubacteriales. 



B. Cells containing sulphur — Order II., Thiobacteriales. 



C. Motile rods in pseudoplasmodial masses embedded in a gelatinous 



matrix and forming highly developed cysts — Order III., Myxo- 

 hactenales. 



Only the first order contains forms of importance in tropical 

 medicine. 



ORDER 1. EUBACTERIALES. 



Definition. — rSchizomycetes which contain neither sulphur nor 

 bact er io-purpur ein . 



Classification. — The Eubacteriales may be divided into famihes 

 as follows:- — 



A. Cells, in free condition, usually globular, in division somewhat ellip- 



tical — Family i, CoccacecB Zopf, 1885, emendavit Migula, 1900. 



B. Cells, long or short, cylindrical, straight; division one direction — 



Family 2, BacillicecB Fischer, 1894. 



C. Cells, spirally curved or representing part of a spiral; division in one 



direction — Family 3, SpirillacecB Migula, 1900. 



D. Cells, surrounded by a sheath and arranged in elongated filaments — 



Family 4, ChlamydohacteriacecB Migula, 1900. 



E. Cells, short or long, cylindrical or filamentous, often clavate, cuneate, 



or irregular, with enclosed granules. Filaments without a sheath — 

 Family 5, MycohacteriacecB Chester, 1901. 



The Chlamydobacteriaceae do not concern us, but the other 

 families require some consideration. 



FAMILY COCCACE.ffi Zopf, 1885, emendavit Migula, 1900. 



Definition,- — Eubacteriales in which the free cells are usually 

 globular, though in division they become somewhat elliptical. 



Type Genus. — Micrococcus HaUier, 1866, emendavit Cohn, 1872, 

 and Winslow and Rogers, 1905. 



Classification. — This family, which contains forms of importance 

 to us, may be divided into two tribes as follows:- — 



A. Parasitic on plants and animals, often growing best anaerobically 



but frequently with difficulty and in small amount, or even not at 

 all, on artificial media; in pairs or chains, generally but not always 

 staining by Gram, and often producing acidity in glucose and lactose 

 media, and when pigmented generally white or orange — ^Tribe I., 

 StveptococcecB Trevisan, 1889, emendavit Winslow and Rogers, 1905. 



B. Facultative parasites or saprophytes growing best under aerobic 



conditions and well on artificial media; in cell groups, packets 

 or zoogloea masses and often Gram-negative, and when pigmented 

 usually yellow or red — Tribe II., MicrococcecB Trevisan, 1889, 

 emendavit Winslow and Rogers, 1905. 



