918 THE SPIROCHJETES 



3 to 9 weeks after the appearance of the chancre ; these comprised a papular eruption 

 on the skin, palmar psoriasis, mucous plaques of the lips, tongue, and palate, and enlarge- 

 ment of the spleen. Occasionally very severe syphilis developed, accompanied by alopecia, 

 skin eruptions, emaciation, paresis of the hind-Umbs, or even death. No lesions of tertiary 

 syphilis were ever found ; but it is to be noted that most of the animals died of broncho- 

 pneumonia before they had been many weeks under observation, and in these tertiary 

 lesions had no time to develop. In macaques secondary lesions were never observed. 

 According to Uhlenhuth and Mulzer (1913) apes are more difficult to infect than rabbits. 

 These workers were successful in conveying human syphilis to rabbits, from rabbits to 

 monkeys, and from a monkey back to rabbits. 



Other Animals. — For studying syphilitic lesions, chimpanzees and rabbits are the most 

 useful experimental animals. Infection can, however, be conveyed to certain other animals, 

 such as pigs, guinea-pigs, rats and mice. According to Tani, Kakishita, and Saito (1930), 

 intratesticular inoculation o{ guinea-pigs gives rise to no obvious lesions, but intracutaneous 

 inoculation, particularly into the perineal fold, is followed in about 11 days by the develop- 

 iment of a swelling which persists for about 7 weeks (see also Mulzer and Hahn 1930). In 

 rats and mice a symptomless infection is usually produced, similar to that often seen in 

 guinea-pigs. The spirochsetes remain latent in the tissues for months, as can be shown 

 by inoculation of rabbits (KoUe and Schlossberger 1926, 1928). Occasionally, however, 

 a local chancre may be produced by inoculation of the scarified skin of the ano-scrotal 

 region (Bessemans and de Potter 1930, 1931). 



Treponema cuniculi 



First observed by Bayon (1913). Responsible for a disease known as " rabbit syphilis." 

 Morphologically very similar to Trep. pallidum, but tends to be slightly longer and thicker. 

 According to Noguchi (1922), dimensions are : length 7-30 /i, average 13 // ; width 0-25 /j, ; 

 length of spirals 1-1-2 /i ; amplitude of spirals 0-6-1 /li. Like Trep. pallidum it stains 

 rose-red with Giemsa. Inoculation of infective material on to the scarified skin of the 

 genital region is followed, after an incubation period of 2 to 8 weeks, by characteristic 

 lesions (see Chapter 81). 



Notes on certain other Treponemata found in the Human or Animal Body. 



Treponema pertenue. — Described by Castellani (1905). Responsible for yaws. Mor- 

 phologically indistinguishable from Trep. pallidum. Exact relation to this organism not 

 yet fully understood. 



Treponema refringens. — This organism was first described by Schaudinn and Hoff- 

 mann (1905) in their original report on the discovery of Trep. pallidum. It was observed 

 in cases of syphilis complicated with such lesions as balanitis, ulcers, and papillomata, 

 and in non-syphilitic lesions such as gonorrhoeal papillomata. Noguchi (1912d) culti- 

 vated it from a condyloma. According to him it grows luxuriantly in the deeper part 

 of an ascitic agar tube, forming hazy colonies, denser than those of Trep. pallidum, which 

 gradually extend from the deeper parts of the tube to the more superficial. It is an 

 anaerobe ; no growth occurs within 2 cm. of the surface. Growth becomes visible in 



4 days at 37° C. and proceeds for some weeks. The addition of fresh tissue is not essential. 

 In culture the organism is 6-24 /t long by 0-5-0-75 ^ broad ; the middle part of the organism 

 is wavy, but the two extremities are more regularly and deeply curved. The ends are 

 pointed. It is non-pathogenic for rabbits and monkeys. 



Treponema calligyrum. — This organism was observed by Noguchi in 1913 in two cases 

 of condyloma, one syphilitic, the other not. Pure cultures were obtained by the ascitic 

 agar stab method. In this medium growth is similar to that of Trep. refringens; the hazy 

 colonies are more dense and diffuse than those of Trep. pallidum. In culture the organisms 

 are 6-14 n long by 0-35-0-4 ^ wide. The primary spirals are regular and deep ; the length 

 of each spiral is 1-6 /i, and the amplitude 1 to r5 /<. The apex of the curve is not 



