LIST OF PLATES 



[iVb<«.— Photographs marked with an asterisk (*) have been kindly lent by the 

 Scientific Press Company; those marked t are taken by permission from the 

 Report of Royal Commission on Sewage Disposal; and those marked J from 

 Reports to the London County Council. ] 



1. A Form of Room Temperature Incubator . 



2. Hot-air Steriliser and Blood-heat Incubator 



3. B. coli communis *j Proteus vulgaris J 



4. B. coli communis ; Gas Production in Gelatine t 



5. Small Centrifuge ; Sedgwick's Sugar-tube . 



6. Air-Plate Culture from Labourer's Cottage 



7. Air-Plate Cultures from Bakehouses 



8. Saccharomyces cerevisice ; Ascospores ; Pathogenic 



Yeast ..... 



9. Buchner's Tube ; Kipp's Apparatus for Anaerobic 



Culture . 



1 0. A Vacuum Method of Anaerobic Culture , 



11. Nitrous Organism; Nitric Organism; Nitrogen- 



fixing Organisms 



12. Nitrogen-fixing Bacteria in Nodule on Rootlet 



of Pea 



13. B. tetani*; B. mycoides*; Streptothrix actinomyces ; 



B. mallei. .... 



14. Sewage Proteus, Organism and Plate Culture | 



15. Sewage Streptococci! and Streptococcus pyogenes* 



16. B. mesentericus, Organism and Plate Culture { 



17. B. anthracis, from Septic Tank Liquor and in 



Gelatine Culture (impression) t 



18. B. tuberculosis (old culture) ; Tubercle Bacilli in 



Cow's Udder .... 



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