1919.] RAINFALL AND FHOLiHOPPER BLIGHT. 159 



on the same four estates iu the following year when the damage 

 "was very severe (Fig. 9). 



Tt will be seen that the following points are again emphasised : — 



Good Year, 1916 (Fig. 8). 



(1.) Dr3' season not severe. January wet. 



(2.) July unusually dry. 



(3.) Indian Summer distinct, but early and not severe. 



Bad Year 1917 (Fig. 9). 



(1.) Dry season long (Decembsr to April) and rather severe. 



(2.) July unusually wet. 



(3.) Indian Summer later and unusually severe. 



Once more the wide spread blight is associated with alternations of 

 wet and dry weather and particularly with a late severe Indian Summer. 



The two estates on which the rainfall remained low during November 

 and December (Fig. 9) are both in the Southern half of the island and 

 in both these the persistence of the damage after the froghopper had 

 <lisappeared and the prevalence of root fungi was very marked. 



Still further coufirniation of the apparent relation is provided by a 

 comparison of the rainfall on good and bad estates during the same 

 year. Fig. 10 shows the rainfall during 1918 on three estates whero 

 practically no damage was reported. Fig. 11 shows, on the contrary, 

 the rainfall on four estates on which the damage was more or loss 

 severe. 



It will be seen that, once again, the wide spread damage is associated 

 with low rainfall during September or October. The difference in the 

 length of the dry season is less marked but just indicated, as it will 

 be seen that all the good estates and only one bad estate had a Januaiy 

 rainfall of over five inches. 



The effect of the rainfall during July is not disbinct but the 

 importance of the Indian Summer drought is still further emphasised 

 when it is seen that the two estates with the lowest rainfall during 

 September were also thoss on which the damage was most severe. 



