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toes to a somewhat serious extent, examples having been received 

 at Kew from two localities, where it is stated to be present in an 

 epidemic condition. 



In the case of potatoes, Dr. Smith has shown that the rapid 

 spread of the disease is caused by insects of various kinds, feeding 

 alternately on diseased and healthy plants. The numerous isolated 

 patches of disease on the fruit and leaves of the tomatoes examined 

 at Kew support this view. To prevent this the plants should be 

 sprayed with Bordeaux mixture containing an insecticide, which 

 would answer the double purpose of warding off insects and 

 preventing the appearance of Phytophthora infestans, Cladosporium 

 fulviim, etc. 



Bacteria have occurred abundantly in the substance of partly 

 ripe tomatoes; hence, owing to the difficulty experienced in tho- 

 roughly removing the glairy coating from the seed, it is highly 

 probable that bacteria would become locked up in this substance 

 as it dried round the seed, and on being released during germina- 

 tion would endanger the crop. Seed, obtained from fruit grown 

 in an infected area should not be used. 



Potato tubers showing the slightest trace of an internal brown 

 ring should not be used for " sets; " in fact, potatoes from an 

 infected district should be avoided. 



Soil that has produced a diseased crop should be treated with 

 gas-lime or with superphosphate of lime. 



Wart disease of Potatoes. The Gardeners Chronicle. Sept. 17, 

 1910, p. 217. 



A pamphlet issued by the Harper-Adams Agricultural College, 

 Newport, Salop, gives an account of experiments made with the 

 object of testing the effect of fungicides on plants affected by Wart 

 disease (Black scab), and of determining which varieties of the Potato 

 are most resistant to the attack of the fungus (Chytridium endo- 

 bioticum^ Percival) responsible for Wart disease. After describing 

 the symptoms now well known of black scab, a brief account 

 is given of the modes by which the fungus spreads from one place 

 to another. The agents responsible for the distribution of the spores 

 are animals, manure, and seed. Thus it has been demonstrated 

 that pigs and poultry straying from infected gardens may carry the 

 spores and thus spread the disease. Again, manure from animals 

 fed on diseased tubers contains the resting spores, and if used on 



