92 GENERAL SYSTEMATIC BACTERIOLOGY 



Brief diagnoses were given of all groups recognized, and type species 

 indicated for the genera. 



Castellani and Chalmers (Manual of Tropical Medicine, 3rd edition, 

 1919), published an unusually detailed classification of the bacteria, 

 carrying the classification out only to include the most important patho- 

 genic organisms which have been described. They use as a general 

 name for the group as a whole, Schizomycetacea. The keys to the vari- 

 ous groups which they recognize are as follows : 



Key to the orders of Schizomycetacea. Castellani and Chalmers (1919) 



A. Cells without sulphur or bacteriopurpurin. 



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. Myxobacteriales 



Key to the Families of Eubacteriales 



A. Cells, in free condition, usually globular, in division somewhat elliptical. 



Family 1. Coccaceae Zopf, 1885, emendavit Migula, 1900 



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



Family 2. Bacillaceae Fischer, 1894 



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



Family 3. Spirillaceae Migula, 1900 



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



Family 4. Chlamydobacteriaceae. Migula, 1900 



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



irregular, with enclosed granules. Filaments without a sheath. 



Family 5. Mycobacteriaceae. Chester, 1901 



Key to the Tribes of Coccaceae 



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



quently 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. Streptococceae. 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. Micrococceae. Trevisan, 1889, emendavit Winslow and Rogers, 1905 



Key to the Genera of Streptococceae 



A. Gram stain negative Neisseria 



B. Gram stain positive: 



I. Pigment absent. 



a. Cells in zoogloea masses, Ascococcus 



