THE BACTERIA AND VIRUSES 



357 



Bacterial Antagonism 



It has long been known that certain Bacteria and Fungi in cuhivation 

 antagonized the growth of others, but the subject assumed practical im- 

 portance in 1929 with the observations of Fleming on the suppression of 



Fig. 343. — Ardisia cienata. Leaves with bacterial pustules 

 around the margins. 



Fig. 344.— Pnr/zo^r/V; hirtella. Transverse section of leaf 

 through a bacterial nodule showing hypertrophied cells 

 filled with bacteria. 



Staphylococcus by a mould, PenicilUiim notatum. The successful application 

 of this discovery to the treatment of some types of bacterial infection aroused 

 widespread interest in the subject and led to the discovery of many other 

 antibiotic substances produced by other moulds and Bacteria. Many of 

 these are too toxic to human subjects to be of medical value, but a few, such 

 as Streptomycin, from Actinomyces griseus, a soil organism, promise to rank 

 in value along with Penicillin. 



