508 SYPHILIS 



human serum, heated at 60C., and placed them in the peritoneal 

 cavity of a monkey (macacus cynomolgus). After an interval of 

 about three weeks, they found in the sacs an abundant growth 

 of spirochsetes morphologically identical with spirochsete pallicla, 

 along with various anaerobic bacteria. They were able to 

 continue such cultures in like conditions, but were unable to 

 obtain any pathogenic effects on inoculating animals with the 

 material from the sacs, and considered that the organisms had 

 became avirulent owing to their conditions of growth. Recently 

 Schereschewsky claims to have obtained impure cultures of the 

 organism in test tubes. He used for this purpose horse serum 

 inspissated at 58 C., and then allowed to undergo autolysis for 

 three days at 37 C. Although abundant growth of spirochaetes 

 was obtained, he was unable to infect animals by means of them, 

 or to obtain any serum reactions which would go to show 

 that the organism was really the spirochsete pallida. 



Transmission of the Disease to Animals. Although various 

 experiments had previously been from time to time made by 

 different observers, in some cases with reported successful result, 

 it is to the papers of Metchnikoff and Roux (1903-5) that we 

 owe most of our knowledge. These observers have carried on a 

 large series of observations, and have shown that the disease can 

 be transmitted to various species of monkey. Of those the 

 anthropoid apes are most susceptible, the chimpanzee being the 

 most suitable for experimental purposes. Their results have 

 been confirmed by Lassar, Neisser, Kraus, and others. The 

 number of experiments on these animals is now very great, and 

 the general result is that the disease has been transmitted by 

 material from all the kinds of syphilitic lesions in which spiro- 

 chaetes have been demonstrated, including even the blood in 

 secondary syphilis and tertiary lesions. Inoculation is usually 

 made by scarification on the eyebrows or genitals ; the sub- 

 cutaneous and other methods of inoculation give negative 

 results. The primary lesion is in the form of an indurated 

 papule or of papules, in every respect resembling the human 

 lesion. Along with this there is a marked enlargement and 

 induration of the corresponding lymphatic glands. The primary 

 lesion appears on an average about thirty days after inoculation, 

 and secondary symptoms develop in rather more than half of the 

 cases after a further period of rather longer duration. These 

 are of the nature of squamous papules on the skin, mucous 

 patches in the mouth, and sometimes palmar psoriasis. As a 

 rule, the secondary manifestations are of a somewhat mild 

 degree, and in no instance up to the present has any tertiary 



