TRANSMISSION OF MICRO-ORGANISMS. 329 



nine eggs, washed these in dilute corrosive sublimate, 

 dried them in wool and introduced the contents of each eo-or 

 into the peritoneal cavity of guinea-pigs. In two cases 

 tuberculosis was set up, the animals dying one and a half 

 months and two and a half months after infection. These 

 experiments, which are absolutely free from objection, 

 conclusively prove that the egg-cell may contain virulent 

 bacteria, and it is easily conceivable that such eggs may 

 develop and the transmission of the parasite take place by 

 direct germinative infection, especially since Maffucci's 

 work shows that such infected eggs are capable of develop- 

 ment. 



Jani, Westermayer, Spano, Walther, Gartner, and quite 

 recently Jakh, have microscopically investigated the bac- 

 terial contents of the reproductive glands, and also inoculated 

 animals with fragments of these organs. With the exception 

 of Gartner's researches these experiments have not added 

 greatly to our knowledge of the hereditary transmission of 

 bacteria. All the experiments of Westermayer were nega- 

 tive. In fourteen cases of well-marked General tuberculosis 

 no tubercle bacilli could be recognised, and inoculation 

 experiments were failures. The experiments of Jakh (10) 

 were more fortunate. Five inoculations with pieces of the 

 male reproductive gland and its product, taken from in- 

 dividuals dead of tuberculosis, gave three positive results. 

 If the gland alone was used, the experiments were always 

 negative, and of three inoculations with pieces of the egg- 

 forming gland one was successful. It may be admitted that 

 these experiments do not really throw much light on the 

 subject of germinative infection, but Gartner's researches 

 are of much greater value. He experimented upon mice, 

 guinea-pigs, rabbits, and canaries, these birds being sus- 

 ceptible to mammalian tubercle bacilli. Having inoculated 

 these animals with bacillus tuberculosis, a careful examination 

 was made of the offspring of such tubercular parents. This 

 method might naturally be expected to give a conclusive 

 answer to the question of hereditary infection, and the 

 following information has been gained from these researches : 

 1. The sperm rarely contains tubercle bacilli — five in 



23 



