THE CUCURBIT WILT.' TRANSMISSION 



143 



FIG. 75. Longitudinal section of a cucumber stem, showing complete invasion 

 and destruction of the inner part of a bundle by Bacillus trncliciphilus. Photo- 

 micrograph by the writer in 1894. 







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V ' - * 







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76. 



FIG. 



FIG. 76. Longitudinal section of a cucumber stem exposing two spiral vessels: 

 one occupied by Bacillus tracheiphilus; the other empty. For details of the bacteria 

 see a thinner section such as Fig. 77 or 78. 



FIG. 77. Detail or Bacilli/* trachei />h/l.<< from a cucumber vessel. Carbol 



