312 MANUAL OF DETERMINATIVE BACTERIOLOGY 



Genus II. Streptococcus Roseiibach.* 



(Rosenbach, Mikroorganismen bei Wundinfektionskrankheiten des Menschen, 1884, 

 22; Arthrostreptokokkus Hueppe, Wiesbaden, 1886, 144; Sphaerococcus Marpmann, 

 Erganzungshefte z. Cent. f. allg. Gesundheitspflege, S, 1889, 121 ; Perroncitoa, Babesia, 

 Schuetzia Trevisan, I generi e le specie delle Batteriacee, 1889, 29; Lactococcus Bei- 

 jerinck, Arch, neerl. d. sci. exactes, Ser. 2, 7, 1901, 213; Hypnococcus Bettencourt et 

 al.. Cent. f. Bakt., I Abt., Orig., 35, 1904, 55; Myxococcus Gonnermann, Oester. u. 

 Ungar. Ztschr. f. Zuckerind. u. Landwirtsch., 36, 1907, 883; not Myxococcus Thaxter, 

 Bot. Gaz., 17, 1892, 404; Melococciis Amiradzibi, Med. Zurn., 4, 1907, 309; Diplo- 

 slreptococcus v. Lingelsheim, in Kolle and Wassermann, Handb. d. path. Mikroorg., 

 2 Aufl., 4, 1912, 494; ? Brachybacterium Troili-Petersson, Cent. f. Bakt., II Abt., 11, 

 1903, 138; Pseudostrephis Enderlein, Sitzb. Gesell. Naturf. Freunde, Berlin, 1917, 309; 

 Planostreptococcus Meyer, Die Zelle der Bakterien, Jena, 1912, 4; Streptus Enderlein, 

 Sitzber. Gesell. Naturf. Freunde, Berlin, 1930, 104; Peptostreptococcus Kluyver and 

 Van Niel, Cent. f. Bakt., II Abt., 94, 1936, 391.) From Greek streptus, flexible or 

 pliant; Greek kokkos, a grain or berry; M. L., a sphere. 



Cells spherical or ovoid, rarely elongated into rods, occurring in pairs, or short or 

 long chains, never in packets or zoogloeal masses. Capsules are not regularly formed, 

 but become conspicuous with some species under certain conditions. Gram-positive, 

 some species decolorizing readily. A few cultures produce a rusty red growth in deep 

 agar stab, or a yellow or orange pigment in starch broth. Growth on artificial media is 

 slight. Agar colonies are small. Surface colonies are translucent. Colonies may 

 be effuse, convex or mucoid. Some species are aided by the addition of native proteins. 

 Mostly facultative anaerobes, with little surface growth in stab cultures. A few are 

 strict anaerobes. Some of the latter attack proteins with production of gas and foul 

 odors. Carbohydrate fermentation by all others is homofermentative, with dextro- 

 rotatory lactic acidas the dominant product, while volatile acids, other volatile products 

 and CO2 are either absent or produced in very small amounts. Inulin is rarely at- 

 tacked. Nitrate is not reduced to nitrite. Not soluble in bile. Common wherever 

 organic matter containing sugars is accumulated. Regularly in the mouth and 

 intestine of man and other animals, dairj- products, fermenting plant juices. Some 

 species are highly pathogenic. 



The type species is Streptococcus pyogenes Rosenbach. 



Note : The classification of streptococci is beset with many difficulties and it seems 

 advisable for the present to accept only such described species about which there is 

 reasonable agreement. With present knowledge, many species which have been sepa- 

 rated can justifiably be considered as identical with older species and have been 

 treated as such here. The descriptions of certain other species do not permit their 

 exact identification now and they have been classed as invalid names with no present 

 significance. It is admitted there are grounds for belief that more than one species 

 may be included in certain of the species described here, but the onus of proof lies 

 with the investigators interested in them. It is hoped that the simplification intro- 

 duced will prove useful as a starting point for the more exact differentiation and 

 description of the species of Streptococcus. The general arrangement used is in 



* Revised by Prof. E. G. D. Murray, McGill University, Montreal, Canada, in con- 

 sultation with Prof. G. J. Hucker, New York State Experiment Station, Geneva, New 

 York and Prof. J. M. Sherman, Cornell University, Ithaca, New York, June, 1938; 

 further revision by Prof. J. M. Sherman, February, 1944. 



