171 



the puparium. Petri suggested that the physiological role 

 of the bacteria in the digestive tract is probably con- 

 nected with the feeding hah it of the larva, which hores in 

 olives, a food which is rich in fats. The larva has to 

 ingest very large quantities of oil in order to extract 

 enough nitrogenous substances necessary for its develop- 

 ment. The "bacteria in the digestive tract may be useful 

 in breaking down the fats and releasing the nitrogen. 



For a description of this organism see Bergey's Manual 

 (5th ed. , page 207), and Bacterium savastanoi in Elliott 

 (1930). 



Buchner, P. 1930 Tier und Pflanze in Symbiose. 900 pp. 



Borntraeger, Berlin. (See page 312. ) 

 Elliott, C. 1930 Manual of bacterial plant pathogens. 



3^-9 PP« Williams and Wilkins Company, Baltimore. (See 



page 198). 

 Petri, L. 1909 Ricerche sapra i batter! intestinal! 



della Mosca olearia'. Memorie R. Staz. Patol. Veg. 



Roma, k, 1-130. 

 Petri, L. 1910 Untersuchungen uber die Darmbakterien 



der Olivenflige. Zentrabl. Bakt. II, 26, 357-3^7- 



Phytomonas solan acearum (Smith) Bergey et al. 



Insect concerned: The potato beetle, Leptihotarsa decim - 

 lineata . 



In warm, moist climates this bacterium attacks potatoes, 

 tohacco, tomatoes, peppers, and other related plants. 

 According to Leach (19^0), the bacteria are found first in 

 the vascular bundles but eventually they enter the paren- 

 chyma cells of the cortex and pith. After spreading 

 through the vascular "bundles of the stolons they reach the 

 tubers where they decay the storage tissues. 



Smith (1896) incriminated the Colorado potato beetle as 

 a disseminator of the disease on the basis of greenhouse 

 experiments. He named the bacterium Bacillus s plana cearum 

 though it is now placed in the genus Phytomonas. For a 

 description of this organism see Bergey's Manual (5th ed. , 

 page 203). 



Leach, J. G-. 19^0 Insect transmission of plant diseases. 



615 pp. McGraw-Hill Book Company, New York. 

 'Smith, E. F. I896 A bacterial disease of the tomato, 



eggplant, and Irish potato ( Bacillus s plana cearum n. sp. ) 

 U. S. Dept. Agr. Div. Physiol, and Path. Bui. 12. 



