E. J. BUTLER § 



during this period that a close watch was kept for it in the 

 countries hitherto free from it. Yet it was not reported to 

 have reached England until 1906, Austria until 1905 or 1906, 

 Hungary until 1908, Belgium until 1909 or 1910, and France 

 actually not until 1913 (though it has been suggested that 

 France was infected earlier and indeed that the English attack 

 came from France). Had spores from the first outbreak 

 been carried hundreds of miles through the air all the 

 gooseberry-growing countries in Europe would have been 

 equally liable to attack in the first few years. Instead of 

 this we have definite statements that all the early 

 Scandinavian attacks came with plants from a nursery in 

 Denmark,! that it was probably distributed all over Austria 

 from a single nursery2 and that nursery distribution from 

 Denmark and Kussia accounts for the whole of the infection of 

 Europe, there being no evidence that Ireland assisted in the 

 spread. Even within England the distribution is not such 

 as would be accounted for by the carrying of the spores for 

 long distances through the air from the first feci of infection in 

 Worcestershire. The fungus is adapted for wind dissemination 

 in so far that it liberates spores freely into the air ; and 

 though these spores are not very long-lived, they would 

 doubtless survive the crossing of the Channel or the Irish Sea 

 without difiiculty. 



Blister-blight has been known on tea in Assam since at least 1868 

 and is one of the most destructive diseases of the crop. 

 It remained entirely confined, so far as is known, to the 

 north-east corner of Assam unti] 1908, when it appeared in 

 the neighbourhood of Darjeeling, and spread with alarming 

 rapidity. Though excellently furnished with the means for 

 short-distance spread, it was unable to ti averse the gap 

 between north-east Assam aiid Darjeeling for 40 years, and 

 has not yet entered the still nearer districts of Cachar and 

 Sylhet. It is peculiarly dependent on climatic conditions and 

 has failed to spread continuously along the tea in the middle 

 and lower parts of Assam. It may have reached Darjeeling 



'Eriksson, J. in Zeilsch. f. Pfianzenkranlcheiten, XVI, 1906, p. S3. 



*Hecke, L. in N aturwissensch. Zeituch. f. Land u. Forsimrtschaft, 1911, p. 51. 



