SCHIZOMYCETES. BACTERIA 



131 



vigorous gray-white film, and no changes are manifest in the 

 substratum. The organism is aerobic and perhaps facultative 

 anaerobic. There is no gas production. 



The contents of the vessels affected are slightly alkaline, and 

 alkaline media are apparently preferred. This organism is sensi- 

 tive to high temperatures, 43" C. or over 

 being fatal in ten minutes. Death results in 

 fifteen minutes in dry air, and the normal 

 life of a culture is from a few weeks to 

 several months. tracheiphilus 



Numerous well-controlled infection experiments have established 

 the causal connection of the bacillus with the symptoms of this 

 disease. 



XII. SOFT ROT OF CARROT AND OTHER VEGETABLES 

 Bacillus carotovorus Jones 



Harding, H. A., and Stewart, F. C. A Bacterial Soft Rot of Certain Cru- 

 ciferous Plants and Amorphophallus simlense. Science, N. S. 16 : 314- 

 315. 1902. 



Harrison, F. C. A Bacterial Disease of the Cauliflower (Brassica oleracea) 

 and Allied Plants. Ont. Agl. Exp. Sta. Built. 137 : 1-28. figs. 1-18. 1904. 



Jones, L. R. A Soft Rot of Carrot and Other Vegetables. Vermont Agl. Exp. 

 Sta. Rept. 13: 299-332. figs. 1-10. 1901. 



Potter, M. C. Ueber eine Bakterienkrankheit der Riiben {Brassica Xapus). 

 Centrbl. f. Bakt., Parasitenk. u. Infektionskr. 1 (Abt. II): 282-2SS, 353- 

 362. 1901. 



Spieckermaxn, A. Beitrag zur Kenntnis der bakteriellen Wundfaulnis der 

 Kulturpflanzen. Landw. Jahrb. 31 : 155-178. 1902. 



Van Hall, C. J. J. Bijdragen tot de Kennis der Bakterieelle Plantenziekten : 

 176-184. 1902. 



Occurrence and effects. This bacillus appears to be one of 

 the most common and widespread of the species parasitic upon 

 plants. It was not accurately studied until 1901, but has since 

 received attention from a number of investigators in different parts 

 of Europe and America. It seems safe to say that it is the chief 

 producer of that type of disease known as soft rot in vegetables. 1 



1 Through the kindness of Mr. H. A. Harding, of the New York Agricul- 

 tural Experiment Station, I have been able to see the proof of a bulletin by 

 H. A. Harding and W. J. Morse on the morphology and cultural characters of 

 this organism. This study establishes in a conclusive manner the fact that many 

 diseases of vegetables previously referred to other organisms are in reality properly 

 caused by this species, and the data here presented are largely based upon the 

 study indicated. 



