606 A MANUAL OF BACTERIOLOGY 



may also be inoculated on the eye or testicle of the 

 rabbit. 



When material from a rhesus monkey inoculated with 

 syphilis is placed in collodion sacs which are introduced 

 into the peritoneal cavity of another monkey, a great 

 multiplication of the organism takes place in the con- 

 tents of the sacs a month after the operation. 1 Noguchi 

 obtained cultures of the S. pallidum by making use of 

 serum water (serum 1 part, water 3 parts), sterilised for 

 fifteen minutes at 100 C. on three days, to which frag- 

 ments of fresh sterile tissue of a rabbit (kidney heart - 

 muscle) were added. Rabbits are inoculated with 

 syphilis in the testicle, and the spirochaete-containing 

 testicular material is employed to inoculate the tubes, 

 which are then incubated at 35-37 C. under strictly 

 anaerobic conditions. Multiplication of the spirochaetes 

 commences forty -eight hours after inoculation. The 

 primary cultures are somewhat difficult to obtain, but 

 once obtained sub -cultivation is easy. Both thick and 

 thin forms of the Spironema were obtained, which 

 Noguchi considers may be distinct varieties. 



Although the central nervous systems of rabbits and 

 monkeys are refractory to direct inoculation with S. 

 pallidum, Noguchi has succeeded in inducing some of the 

 symptoms (convulsions) and lesions of general paralysis 

 in these animals by the following method. Intravenous 

 inoculations of dead /Spironema cultures were given every 

 five days over a period of five months, an interval of five 

 months was then allowed to elapse, and finally the living 

 spirochaetes were introduced into the brain, subdurally 

 or intra-cerebrally. 



Levaditi and Marie 2 hold that two distinct races of 

 S. pallidum exist, one the ordinary or dermotropic form, 



1 Levaditi and Mclntosh, Ann. de Vlnst. Pasteur, xxi, 1907. 



2 Ann. de TInst. Pasteur, vol. xxxiii, 1919, p. 741. 



