148 MICROBES AND TOXINS 



infected with the spirochsete of Marchoux and Salimbeni the 

 parasite may penetrate the egg, particularly the yolk, and in 

 this case inheritance may occur from vertebrate to vertebrate. 

 Hygiene has to take account of these facts : to abolish a 

 parasite it is insufficient to destroy it in the vertebrate ; the 

 invertebrate host also has to be abolished since it is capable of 

 transmitting the parasite to its descendants, the egg of the 

 infected insect preserving the disease in nature somewhat as the 

 anthrax spore keeps alive anthrax. 



Schaudinn considered the spirochaete which he discovered 

 in syphilis to be a protozoon. Now the clinicians regard 

 syphilis as a disease which can be inherited. The case of new- 

 born infants with syphilis does not alone prove an hereditary 

 infection, the spirochaete being very motile might be transmitted 

 from the mother to the foetus through some lesion of the 

 placenta. Congenital syphilis is by no means necessarily a 

 syphilis by conception. But from certain observed facts such 

 true inheritance is very probable. The spirochaete has the 

 power of spontaneously penetrating cells : it has even a 

 predilection for epithelial cells : further, although there are 

 no certain observations of its presence in a spermatozoon, it has 

 been seen in the spermatic tubules in close relation to the 

 epithelial cells (in congenitally syphilitic boys), and it has been 

 seen (Levaditi and Sauvage) in the protoplasm of the ovarian 

 follicles of female children. Are infected ova in the woman 

 capable of fertilisation, and, if fertilised, capable of normal 

 development? It seems possible in view of the clinical facts and 

 by analogy with the case of the tick Ornithodorus, whose eggs 

 infected with spirilla give rise to larvae which as adults are 

 capable of conveying the infection. 



To sum up, we know from Finger and Landsteiner's experi- 

 ments that the semen of an adult syphilitic is, as a substance, 

 capable of producing syphilis, and we know that the congenital 

 syphilitic of the male sex shows the parasite developing in the 

 seminal gland in contact with the epithelial cells, but no one 

 has ever seen a spirochaete in an adult spermatozoon. In the 

 female subject there can be no doubt of the possibility of 



