CULTIVATION OF THE SPIROCHÆTA PALLIDA

Since Schaudinn several years ago discovered the Spirochæta pallida, many attempts have been made to grow the organism on artificial media, but only recently has any degree of success been obtained. Schereschewsky¹ observed multiplication of the spirochete in pure horse serum. This medium heated to 58 or 60° C. for an hour or more becomes gelatinous, though it remains perfectly clear. Material obtained from a syphilitic papule or condyloma is immersed in this fluid and placed under strict anaerobic conditions in the incubator. After a number of days the culture is examined and by both the staining method and dark-ground illumination a notable increase in the number of organisms is seen. He recommends the dark-ground illuminator as very satisfactory and easily recognizes the Spirochæta pallida by this method. In a more recent paper² he gives the results of more extensive studies. In the first culture shortly after inoculation