XV] ANAEROBIC BACILLI 399 



that after the multiplication of the bacilli in the early phases 

 has reached its climax spores begin to be formed, and it is 

 these which prevail in the lymph of the later phases. This 

 would well accord with the known facts concerning the 

 preservation of the active principles, for it is established 

 that the active principle of vaccine is preserved in glycerine, 

 although as is also known pure glycerine acting for long 

 times is a germicide for cocci and sporeless bacilli ; likewise 

 lymph dried in thin layers on points preserves its efHcacy 

 for long periods, although such prolonged drying would kill 

 all but spores. 



Large numbers of species of microbes, have been described 

 as occurring in vaccine lymph : cocci, bacilli, torula, and 

 there is no difficulty in demonstrating by film specimens and 

 particularly by culture their occurrence in lymph collected 

 in the usual fashion — i.e. without special precautions in 

 avoiding surface or epidemic admixtures. My experience, 

 extending over a very considerable number of experiments, 

 is this, that from carefully dnd properly collected vaccine 

 lymph (humanised) such as is sent out by the Vaccine 

 Department of the Local Government Board, and such as 

 it is possible to collect aseptically from a calf vesicle (after 

 scraping off the crust) from a percentage of tubes containing 

 proved active vaccinia, no cultures are obtainable in the 

 ordinary media (nutrient gelatine, nutrient Agar, sugar 

 gelatine, sugar Agar, solidified serum) although the cocci and 

 bacilli which are present and have been described in many 

 samples of vaccinia are easily cultivable in these media : 

 staphylococcus albus and cereus, staphylococcus aureus, 

 bacillus mesentericus, torula, &c. From my own observa- 

 tions, which are in complete accord with those of Dr. Cope- 

 man, I maintain that none of those ordinarily cultivable 

 microbes are an essential inhabitant in vaccinia, and can have 



