SUPPURA TION. ! 85 identical with those of the preceding species, it seems convenient to describe them together, pointing out such FIG. 50.—Staphylococcus pyogenes aureus, from an agar-agar culture; x 1000 (Gunther). differences as occur step by step. In doing this, how- ever, it must not be forgotten that, although the Staphy- lococcus albus has been described first, the Staphylococcus aureus is the more common organism of the suppurative diseases. Although they had been seen earlier by several ob- servers, the staphylococci were not isolated and care- fully described until 1884, when Rosenbach worked upon them. The results of his study, followed by Passet and a host of others, have now given us pretty accurate information about them. The cocci are distributed rather sparingly in nature, seeming not to find a purely saprophytic existence a suitable one. They occur, however, wherever man and animals have been, and can be found in the dust of houses, hospitals, and especially surgical wards where proper precautions are not exercised. They are common upon the skin, they live in the nose, mouth, eyes, and ears of man, they are nearly always beneath the finger- nails, and they sometimes occur in the feces, especially in children.