20 ] The Classification of Lower Organisms 



3. Not requiring carbohydrates. 



4. Oxidizing alcohol to acetic 



acid, and acetic acid to CO2 



and H2O Family 12. Acetobacteriacea. 



4. Not as above; many examples 



strictly autotrophic Family 13. Nitrobagteriacea. 



Family 1. Micrococcacea [Micrococcaceae] Pribram in Jour. Bact. 18: 370, 385 

 (1929). Family Coccaceae Zopf 1884; but the genus Coccus is a scale insect. Gram 

 positive spheres producing packets or irregular masses. Micrococcus, saprophytic or 

 parasitic, producing irregular masses of cells; the pathogenic species have been treated 

 as a separate genus Staphylococcus. Sarcina, saprophytic or commensal spheres pro- 

 ducing packets. 



Family 2. Neisseriacea [Neisseriaceae] Prevot ex Bergey et al. Manual ed. 5 : 278 

 (1938). Family Neisseriacees Prevot in Ann. Sci. Nat. Bot. ser. 10, 15: 119 (1933). 

 Obligate parasites, the Gram negative spherical cells occurring chiefly in pairs within 

 leucocytes in the lesions of disease. Neisseria gonorrhoeae, the gonococcus; A^. ]Veich- 

 selbaumii Trevisan {N. intracellularis, N. meningitidis, Auctt.), the meningococcus. 



Family 3. Corynebacteriacea [Corynebacteriaceae] Lehmann and Neumann 1907. 

 Family Corynebacteriidae Enderlein in Sitzber. Gess. naturf. Freunde Berlin (1917) : 

 314. Family Lactobacillaceae Winslow et al. in Jour. Bact. 2: 561 (1917). Family 

 Lactobacteriaceae Orla-Jensen 1921. Family Leptotrichaceae Pribram in Jour. Bact. 

 18: 372 (1929), not family Leptotrichacei Schroter 1886. Gram positive rods, or 

 spheres dividing in one plane and producing chains, non-motile. 



Streptococcus, spheres in chains; saprophytes in milk, involved in the making of 

 butter and cheese; and commensals and serious pathogens causing, for example, 

 abscesses, septicemia, erysipelas, and pneumonia. 



Diplococcus, spheres usually in pairs, encapsulated. D. pneumoniae occurs in many 

 immunologically distinct races which are the usual causes of pneumonia. 



Lactobacillus, rods, microaerophilic, producing lactic acid. In milk, involved in 

 the making of butter and cheese; in the oral cavity, being the usual agent of dental 

 caries (Rosebury, Linton, and Buchbinder, 1929); common in sewage. 



Leptotrichia, rods which become exceptionally long before dividing. Oral cavity 

 of man and beasts. 



Corynebacterium, rods, becoming club-shaped, staining in a banded pattern. The 

 type species is the agent of diphtheria, C. diphthcriae; the genus includes also many 

 harmless commensals important only as making diagnosis difficult. The cells divide 

 in an exceptional fashion, by breaking violently from one side to the other near one 

 end; the cut-off end swings around beside the main body and proceeds to grow. 

 Repeated division in this manner produces clusters of parallel cells (Park, \V'iliiams, 

 and Krumweide, 1924). 



Family 4. Rickettsiacea [Rickettsiaceae] Pinkerton 1936. Families Bartonellaceae 

 Gieszszykiewicz 1939 and Chlamydozoaceae Moshkovsky 1945. Minute obligate intra- 

 cellular parasites of varied form, commonly Gram negative but with Gram positive 

 granules. 



There have been many observations of bodies of the characters stated, but a satis- 

 factory classification of them is not yet possible. Howard Taylor Ricketts showed 

 that Rocky Mountain spotted fever is transmitted by the tick Dcrmocentor, and 

 observed, in the cells of diseased tissues, minute irregularly staining bodies; in 1910, 



