456 



TR YPA NOSOMIDm 



of the whole body. The periplast is continued as long delicate 

 processes at each end, which are considered by some to be flagella. 



Krzysztalowicz and Siedlecki say that not far from the middle 

 the body may be nearly straight, and a clear spot can be observed 

 which they think is a nucleus ; but it might correspond to the similar 

 area in 5. duttoni. They also describe male and female gametes 

 and conjugation, which they think leads to the formation of a cyst 

 or spore, which may be carried via the blood stream to different 

 parts of the body, and there develop into Treponemata. 



The parasite is found in the primary sores and in the secondary 

 lesions, but is very difficult to detect in tertiary eruptions, though 

 it is abundantly present in the liver, spleen, decidua, the placental 

 villi, the umbilical cord of syphilitic foetuses, and infants. 



It is distinguished from other spirochaetes (S. refringens) which 

 may be met with on ulcerated surfaces by difficulty in staining; 

 number, character, and permanence of the spirals; the terminal 

 prolongations; absence of an undulating membrane; minute size 

 and delicacy. 



Inoculation.— S^^philis can be inoculated into chimpanzees (as 

 shown by Metchnikoff and Roux) and other monkeys, and 

 T. pallidum can be found in the lesions so caused, the incubation 

 being fifteen to forty-nine days, average thirty days, for the primary 

 sore; and nineteen to sixty- one days, average thirty- three da^^s, for 

 the secondary eruption after the primary have appeared. In the lower 

 monkeys the lesion remains localized to the seat of the inoculation. 



Cultivation. — Schereschewsky has cultivated, with a certain degree 

 of success, T. pallidum on a medium of horse serum, brought to a 

 gelatinous consistence by heating to 60° C, and partly autolyzed by 

 keeping in an incubator at 37° C. for three days. Later Mtihlens 

 and Hartmann also cultivated it, Hartmann inoculating a pure 

 culture with success in the testicles of a rabbit, and more recently it 

 was grown by Noguchi quite successfully, as described above for 

 Spiroschaudinnia, and he has also been successful in reproducing the 

 disease in monkeys by inoculation of the pure culture. The monkeys 

 present a positive Wassermann reaction two weeks after inoculation. 

 Noguchi has made the important observation that there are several 

 varieties of T. pallidum ; he distinguishes a normal type of medium 

 thickness, a thick type, and a thin iy^Q. Inoculated in the testicles 

 of rabbits, the normal type gives rise to a diffuse induration. Which 

 develops the third Week after inoculation; the thick type gives rise 

 to several small hard nodules, which develop slowly; the thin type 

 induces a diffuse swelling, which develops very quickly, ten to 

 fourteen days after inoculation. It is interesting to note that Mott, 

 several years ago, suggested- — ^on clinical and pathological grounds — 

 that there might be more than one variety of T. pallidum. 



Biological Reactions.— By heating the cultures to 60° C. Noguchi 

 has produced a product which he calls luetine, by means of which 

 a cutaneous reaction can be obtained in syphilitic patients. 



Life-History. — Unknown. 



