DISEASES CAUSED BY SPIROCHiBTES 



607 



original blood for as long as forty days, and call attention to the fact 

 that the length of time for which they may be kept alive depends to a 

 great extent upon the stage of fever at which the blood is removed from 

 the patient. They do not, however, beUeve that extensive multiplica- 

 tion, or, in other words, actual cultivation, had taken place in their 

 experiments. Norris, Pappenheimer, and Flournoy, on the other hand, 

 have obtained positive evidence of multiphcation of the spirochsetes in 

 fluid media. They obtained their cultures by inoculating a few drops 

 of spirochaetal rat blood into 3 to 5 c.c. of citrated human or rat blood. 

 Smears made froin these tubes, after preservation for twenty-four hours 

 at room temperatm-e, showed the microorganisms in greater number 



Fig. 134. — Spirochete of Relapsing Fever. (From preparation furnished 

 by Dr. G. N. Calkins.) 



than in the original infected blood. A similar multiphcation could be 

 observed in transfers made from these "first-generation" tubes to other 

 tubes of citrated blood. Attempts at cultivation for a third generation, 

 however, failed. 



Noguchii has lately successfully cultivated the spirochaete of Ober- 

 meier in ascitic fluid containing a piece of sterile rabbit's kidney and a 

 few drops of citrated blood under anaerobic conditions. 



Four different, probably distinct varieties of spirochaete have been 

 described in cormection with relapsing fever, all of which have been 

 cultivated by Noguchi by means of this method. The first is known as 

 the spirochaete of Obermeier mentioned above. Probably distinct 



' Noguchi, Jour. Exp. Med., xvii, 1913. 



