During the past decade numerous efforts have been made to devise a satisfactory classification of streptococci, most of them being based on the carbohydrate fermentation test. The most notable of the studies have been those of Gordon,1 S. Andrewes and Horder,2 Winslow,3 and Floyd and Wolbach.4 The reliability of the fermentation test has been questioned by Walker5 and others. Schottmueller's6 classification of streptococci, based on the appearance of the colonies on blood-agar, is at present perhaps the most practical, if not the most accurate classification of these bacteria. He divides them as follows :
Streptococcus haemolyticus (longus, pyogenes), which on blood-agar produces a clear zone of hemolysis about the colony; morphologically, it appears in chains of round or slightly oval cocci ; this is the type almost constantly found in erysipelas, complications of scarlet fever and various suppurative processes of streptococcus origin.
CECIL RL. STREPTOCOCCUS VIRIDANS IN ITS RELATION TO INFECTIONS OF THE UPPER RESPIRATORY TRACT. Arch Intern Med (Chic). 1915;XV(1):150-168. doi:10.1001/archinte.1915.00070190153010